Update notebook buttons

Author: davewhipp

L1/a-taste-of-python.ipynb

@@ -12,7 +12,8 @@
     "University of Helsinki students are encouraged to use the CSC Notebooks platform.<br/>\n",
     "<a href=\"https://notebooks.csc.fi/#/blueprint/7e62ac3bddf74483b7ac7333721630e2\"><img alt=\"CSC badge\"     src=\"https://img.shields.io/badge/launch-CSC%20notebook-blue.svg\" style=\"vertical-align:text-bottom\"></a>\n",
     "\n",
-    "We will start our Python lesson by learning a bit of the basic operations you can perform using Python.\n",
+    "Others can follow the lesson and fill in their student notebooks using Binder.<br/>\n",
+    "<a href=\"https://mybinder.org/v2/gh/geo-python/notebooks/master?urlpath=lab/tree/L1/a-taste-of-python.ipynb\"><img alt=\"Binder badge\" src=\"https://img.shields.io/badge/launch-binder-red.svg\" style=\"vertical-align:text-bottom\"></a>\n",
     "\n",
     "## General information\n",
     "\n",

L2/Python-basic-elements.ipynb

@@ -6,12 +6,11 @@
    "source": [
     "# Basic elements of Python\n",
     "\n",
-    "```{attention}\n",
     "University of Helsinki students are encouraged to use the CSC Notebooks platform.<br/>\n",
     "<a href=\"https://notebooks.csc.fi/#/blueprint/7e62ac3bddf74483b7ac7333721630e2\"><img alt=\"CSC badge\" src=\"https://img.shields.io/badge/launch-CSC%20notebook-blue.svg\" style=\"vertical-align:text-bottom\"></a>\n",
-    "```\n",
     "\n",
-    "In this lesson we will revisit data types, learn how data can be stored in Python lists, and some useful ways of using and modifying Python lists."
+    "Others can follow the lesson and fill in their student notebooks using Binder.<br/>\n",
+    "<a href=\"https://mybinder.org/v2/gh/geo-python/notebooks/master?urlpath=lab/tree/L2/Python-basic-elements.ipynb\"><img alt=\"Binder badge\" src=\"https://img.shields.io/badge/launch-binder-red.svg\" style=\"vertical-align:text-bottom\"></a>"
    ]
   },
   {

L3/conditional-statements.ipynb

@@ -9,7 +9,8 @@
     "University of Helsinki students are encouraged to use the CSC Notebooks platform.<br/>\n",
     "<a href=\"https://notebooks.csc.fi/#/blueprint/7e62ac3bddf74483b7ac7333721630e2\"><img alt=\"CSC badge\" src=\"https://img.shields.io/badge/launch-CSC%20notebook-blue.svg\" style=\"vertical-align:text-bottom\"></a>\n",
     "\n",
-    "In this lesson we will learn how to make choices in our code using conditional statements (`if`, `elif`, `else`) and Boolean values (`True`, `False`). \n",
+    "Others can follow the lesson and fill in their student notebooks using Binder.<br/>\n",
+    "<a href=\"https://mybinder.org/v2/gh/geo-python/notebooks/master?urlpath=lab/tree/L3/conditional-statements.ipynb\"><img alt=\"Binder badge\" src=\"https://img.shields.io/badge/launch-binder-red.svg\" style=\"vertical-align:text-bottom\"></a>\n",
     "\n",
     "\n",
     "## Sources\n",
@@ -424,7 +425,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.7.3"
+   "version": "3.7.4"
   }
  },
  "nbformat": 4,

L3/for-loops.ipynb

@@ -9,7 +9,8 @@
     "University of Helsinki students are encouraged to use the CSC Notebooks platform.<br/>\n",
     "<a href=\"https://notebooks.csc.fi/#/blueprint/7e62ac3bddf74483b7ac7333721630e2\"><img alt=\"CSC badge\" src=\"https://img.shields.io/badge/launch-CSC%20notebook-blue.svg\" style=\"vertical-align:text-bottom\"></a>\n",
     "\n",
-    "In this lesson we introduce loops as a way of repeating parts of a script, such as iterating over all of the items in a Python list and performing a calculation on each item.\n",
+    "Others can follow the lesson and fill in their student notebooks using Binder.<br/>\n",
+    "<a href=\"https://mybinder.org/v2/gh/geo-python/notebooks/master?urlpath=lab/tree/L3/for-loops.ipynb\"><img alt=\"Binder badge\" src=\"https://img.shields.io/badge/launch-binder-red.svg\" style=\"vertical-align:text-bottom\"></a>\n",
     "\n",
     "## Sources\n",
     "\n",