Issue #1323530 by tstoeckler: Document libraries_get_version() pattern matching.

CHANGELOG.txt

 
 Libraries 7.x-2.x, xxxx-xx-xx
 -----------------------------
+#1323530 by tstoeckler: Document libraries_get_version() pattern matching.
 #1325524 by sun, Rob Loach, tstoeckler: Statically cache libraries_detect().
 #1321372 by Rob Loach: Provide a 'post-load' callback group.
 #1205854 by tstoeckler, sun: Test library caching.

libraries.api.php

@@ -51,7 +51,10 @@
  *     - file: The filename to parse for the version, relative to the library
  *       path. For example: 'docs/changelog.txt'.
  *     - pattern: A string containing a regular expression (PCRE) to match the
- *       library version. For example: '@version\s+([0-9a-zA-Z\.-]+)@'.
+ *       library version. For example: '@version\s+([0-9a-zA-Z\.-]+)@'. Note
+ *       that the returned version is not the match of the entire pattern (i.e.
+ *       '@version 1.2.3' in the above example) but the match of the first
+ *       sub-pattern (i.e. '1.2.3' in the above example).
  *     - lines: (optional) The maximum number of lines to search the pattern in.
  *       Defaults to 20.
  *     - cols: (optional) The maximum number of characters per line to take into

libraries.module

@@ -703,7 +703,10 @@ function libraries_load_files($library) {
  *   - file: The filename to parse for the version, relative to the library
  *     path. For example: 'docs/changelog.txt'.
  *   - pattern: A string containing a regular expression (PCRE) to match the
- *     library version. For example: '@version\s+([0-9a-zA-Z\.-]+)@'.
+ *     library version. For example: '@version\s+([0-9a-zA-Z\.-]+)@'. Note that
+ *     the returned version is not the match of the entire pattern (i.e.
+ *     '@version 1.2.3' in the above example) but the match of the first
+ *     sub-pattern (i.e. '1.2.3' in the above example).
  *   - lines: (optional) The maximum number of lines to search the pattern in.
  *     Defaults to 20.
  *   - cols: (optional) The maximum number of characters per line to take into