Reimplemented #23

The docblock detection a little more strict and requires /** as a comment starter
Added support for constants and properties
Added g:phpcomplete_parse_docblock_comments option to enable this feature
Added the return type to 'menu' for methods
Added the property type for the 'menu' for properties
Moved the comment extraction, parsing and formatting to separate methods
Clear leftover from rename
Fix static property completion for user classes.

When comleting a line like: self:$some_ the plugin failed to return
static properties starting with "some_".
This patch also changes the ordering of returned completions. Now the whole
list is sorted by vim as a whole (and vim puts $ on top).
Added tests to test filtering.
Merge branch 'master' into develop