minor #9206 Added links to the roadmap of each Symfony version (javiereguiluz)

This PR was squashed before being merged into the 2.7 branch (closes #9206).

Discussion
----------

Added links to the roadmap of each Symfony version

Commits
-------

9d7acc2 Added links to the roadmap of each Symfony version

Author: javiereguiluz

contributing/community/releases.rst

@@ -110,31 +110,31 @@ Below is the schedule for the first few versions that use this release model:
 
 .. _version-history:
 
-=======  ==============  =======  ========================  ===========
-Version  Feature Freeze  Release  End of Maintenance        End of Life
-=======  ==============  =======  ========================  ===========
-2.0      05/2011         07/2011  03/2013 (20 months)       09/2013
-2.1      07/2012         09/2012  05/2013 (9 months)        11/2013
-2.2      01/2013         03/2013  11/2013 (8 months)        05/2014
-**2.3**  03/2013         05/2013  05/2016 (36 months)       05/2017
-2.4      09/2013         11/2013  09/2014 (10 months [1]_)  01/2015
-2.5      03/2014         05/2014  01/2015 (8 months)        07/2015
-2.6      09/2014         11/2014  07/2015 (8 months)        01/2016
-**2.7**  03/2015         05/2015  05/2018 (36 months)       05/2019
-**2.8**  09/2015         11/2015  11/2018 (36 months [2]_)  11/2019
-3.0      09/2015         11/2015  07/2016 (8 months) [3]_)  01/2017
-3.1      03/2016         05/2016  01/2017 (8 months)        07/2017
-3.2      09/2016         11/2016  07/2017 (8 months)        01/2018
-3.3      03/2017         05/2017  01/2018 (8 months)        07/2018
-**3.4**  09/2017         11/2017  11/2020 (36 months)       11/2021
-4.0      09/2017         11/2017  07/2018 (8 months)        01/2019
-4.1      03/2018         05/2018  01/2019 (8 months)        07/2019
-4.2      09/2018         11/2018  07/2019 (8 months)        01/2020
-4.3      03/2019         05/2019  01/2020 (8 months)        07/2020
-**4.4**  09/2019         11/2019  11/2022 (36 months)       11/2023
-5.0      09/2019         11/2019  07/2020 (8 months)        01/2021
-...      ...             ...      ...                       ...
-=======  ==============  =======  ========================  ===========
+============  ==============  =======  ========================  ===========
+Version       Feature Freeze  Release  End of Maintenance        End of Life
+============  ==============  =======  ========================  ===========
+`2.0`_        05/2011         07/2011  03/2013 (20 months)       09/2013
+`2.1`_        07/2012         09/2012  05/2013 (9 months)        11/2013
+`2.2`_        01/2013         03/2013  11/2013 (8 months)        05/2014
+`2.3`_ (LTS)  03/2013         05/2013  05/2016 (36 months)       05/2017
+`2.4`_        09/2013         11/2013  09/2014 (10 months [1]_)  01/2015
+`2.5`_        03/2014         05/2014  01/2015 (8 months)        07/2015
+`2.6`_        09/2014         11/2014  07/2015 (8 months)        01/2016
+`2.7`_ (LTS)  03/2015         05/2015  05/2018 (36 months)       05/2019
+`2.8`_ (LTS)  09/2015         11/2015  11/2018 (36 months [2]_)  11/2019
+`3.0`_        09/2015         11/2015  07/2016 (8 months) [3]_)  01/2017
+`3.1`_        03/2016         05/2016  01/2017 (8 months)        07/2017
+`3.2`_        09/2016         11/2016  07/2017 (8 months)        01/2018
+`3.3`_        03/2017         05/2017  01/2018 (8 months)        07/2018
+`3.4`_ (LTS)  09/2017         11/2017  11/2020 (36 months)       11/2021
+`4.0`_        09/2017         11/2017  07/2018 (8 months)        01/2019
+`4.1`_        03/2018         05/2018  01/2019 (8 months)        07/2019
+`4.2`_        09/2018         11/2018  07/2019 (8 months)        01/2020
+`4.3`_        03/2019         05/2019  01/2020 (8 months)        07/2020
+`4.4`_ (LTS)  09/2019         11/2019  11/2022 (36 months)       11/2023
+`5.0`_        09/2019         11/2019  07/2020 (8 months)        01/2021
+...           ...             ...      ...                       ...
+============  ==============  =======  ========================  ===========
 
 .. [1] Symfony 2.4 maintenance has been `extended to September 2014`_.
 .. [2] Symfony 2.8 is the last version of the Symfony 2.x branch.
@@ -193,3 +193,23 @@ version is published every two years and there is a year to upgrade.
 .. _roadmap notification: https://symfony.com/roadmap
 .. _extended to September 2014: https://symfony.com/blog/extended-maintenance-for-symfony-2-4
 .. _timeline calculator: https://symfony.com/roadmap#checker
+.. _`2.0`: https://symfony.com/roadmap?version=2.0
+.. _`2.1`: https://symfony.com/roadmap?version=2.1
+.. _`2.2`: https://symfony.com/roadmap?version=2.2
+.. _`2.3`: https://symfony.com/roadmap?version=2.3
+.. _`2.4`: https://symfony.com/roadmap?version=2.4
+.. _`2.5`: https://symfony.com/roadmap?version=2.5
+.. _`2.6`: https://symfony.com/roadmap?version=2.6
+.. _`2.7`: https://symfony.com/roadmap?version=2.7
+.. _`2.8`: https://symfony.com/roadmap?version=2.8
+.. _`3.0`: https://symfony.com/roadmap?version=3.0
+.. _`3.1`: https://symfony.com/roadmap?version=3.1
+.. _`3.2`: https://symfony.com/roadmap?version=3.2
+.. _`3.3`: https://symfony.com/roadmap?version=3.3
+.. _`3.4`: https://symfony.com/roadmap?version=3.4
+.. _`4.0`: https://symfony.com/roadmap?version=4.0
+.. _`4.1`: https://symfony.com/roadmap?version=4.1
+.. _`4.2`: https://symfony.com/roadmap?version=4.2
+.. _`4.3`: https://symfony.com/roadmap?version=4.3
+.. _`4.4`: https://symfony.com/roadmap?version=4.4
+.. _`5.0`: https://symfony.com/roadmap?version=5.0