Added inline tags section.

phpDocumentor supports inline tags in the description. Which has been
part of the standard usage for docblocks. This inline description is
supported by most editors supporting php. Therefor the inline tags
belong in this spec.

Author: jaapio

proposed/phpdoc.md

@@ -10,6 +10,7 @@ PSR-5: PHPDoc
 - [5. The PHPDoc Format](#5-the-phpdoc-format)
   - [5.1. Summary](#51-summary)
   - [5.2. Description](#52-description)
+    - [5.2.1 Inline tags](#521-inline-tags)
   - [5.3. Tags](#53-tags)
     - [5.3.1. Tag Name](#531-tag-name)
   - [5.4. Examples](#54-examples)
@@ -237,6 +238,33 @@ Common uses for the Description:
 * To provide a set of common use cases or scenarios in which the "Structural
   Element" may be applied
 
+#### 5.2.1 Inline tags
+
+A description MAY contain inline tags. Inline tags MUST follow the specification of
+tags with the same syntax. An inline tag MUST start with `{@` and MUST with `}`
+
+```php
+  /** 
+   * Summary.
+   * 
+   * This is a description with an inline tag {@tag rest of the tag format}
+   */
+```
+
+Inline tags are only covering regular tags and SHALL NOT cover _Annotation_ tags.
+
+As inline tags are always closed with a `}` developers cannot use this char in a 
+description. To overcome this issue parsers MUST support escape char `{` followed
+by `}` to be interpreted as a single `}` 
+
+```php
+   /**
+    * Summary.
+    *
+    * This is a description with an inline tag {@tag show case {} escape of ending char}
+    */
+```
+
 ### 5.3. Tags
 
 Tags supply concise metadata for a "Structural Element". Each tag starts on a
@@ -253,8 +281,8 @@ format, as dictated by the specific tag.
 > _type_ (`string`), variable name (`$argument1`),  and description (`This is a
 > parameter.`).
 
-The description MUST support Markdown as a formatting language.  The
-description of the tag MAY start on the same line or next line.  The following
+The description MUST support Markdown as a formatting language. The
+description of the tag MAY start on the same line or next line. The following
 tags are semantically identical:
 
 ```php