Finish 2.3
Fix AttributeError on close
Revert "Fix AttributeError on close"

This reverts commit 9a63332fe31aae5a640163de1f9229f83ee85081.
Bump version to 2.4.dev (next development)
Fix default encoding on windows: always use UTF-8
Make use of the new function key
Remove useless warning
Fix brief documentation of modes and panels

This brief documentation can be used as a tooltip for modes/panels menu.
Code completion: new item type: INSTANCEELEMENT
Fix pyqode main docstring (uniformised with other pyqode namespace packages)
Make use of the new find_symbol_pos function
Renamed qidle example into pynotepad

QIdle is the name of an application I am currently developing and I would prefer to avoid to bring confusion so it is better to renamed the example into something else. As we already have a notepad example in pyqode.core, it makes sense to name the example pynotepad (for python notepad)
Make use of the splittable tab widget in pynotepad

Also make some adaptations to easily instantiate a PyCodeEdit with default parameters (the backend will start in the constructor)
Fix PyCodeEdit test config
Implement clone_settings and propagete new values to clones
Fix unindent selection (selection was lost after unindent)
Merge branch 'develop'
Merge remote-tracking branch 'origin/master'