feature - Improve method tag parsing

This is an update based on the original repository, I just cherry-picked
some code.

https://github.com/phpDocumentor/ReflectionDocBlock/blob/master/src/DocBlock/Tags/Method.php

This includes:
- phpDocumentor@e9454d8
- phpDocumentor@e9454d8

Author: JeppeKnockaert

src/Barryvdh/Reflection/DocBlock/Tag/MethodTag.php

@@ -76,7 +76,15 @@ public function setContent($content)
                 )?
                 # Return type
                 (?:
-                    ([\w\|_\\\\]+)
+                    (
+                        (?:[\w\|_\\\\]*\$this[\w\|_\\\\]*)
+                        |
+                        (?:
+                            (?:[\w\|_\\\\]+)
+                            # array notation
+                            (?:\[\])*
+                        )*
+                    )
                     \s+
                 )?
                 # Legacy method name (not captured)