Add ishikawa/python-plist-parser as module in "Lib/"

State as of 9d924a1c665e73c1b6ac1e7fe003cedbeb2a5c9f
(https://github.com/ishikawa/python-plist-parser/tree/9d924a1c665e73c1b6ac1e7fe003cedbeb2a5c9f)
PEP8 for plist parser
plist_parser code adjustments
Use plist_parser as an alternative if xml.parsers.expat is not available

Said module is used by plistlib.readPlistFromString and won't work if the
module could not be imported on certain Linux dists.

Updates #19
Add example link for YAML syntax definitions
Add tip to update auto_complete_triggers setting for better user experience
Move info when creating completions from the console to the status bar

It doesn't help having thousands of lines in the console when you don't care about it as end user anyway. Furthermore, in the status bar you can actually see this stuff directly if you actually care about it.
Merge branch 'origin/alternative_plist_loader'