Fix open file action in example when run with pyside
Renamed ICON_XXX into ACTION_XXX
Added NEXT and PREVIOUS actions (icons and shortcuts)
Revert the previous commit (I forgot that those actions are defined by the ui scipt)
DelayJobRunner: add a way to cancel requested jobs
SearchPanel: fix multithread issues
Refactoring (hide internal methods)
Fix typo
Implement search results navigation  + fix draw order of occurrences decorations
Add navigation shortcuts to the editor context menu
DelayJobRunner: add a way to request an synchronous job
Remove debug messages
Search&Replace: implement replace and replace all
close #42:
  - Added a warning about thread and gui
  - Modifty example with a thread safe implementation.
Minor refactorisation
SearchAndReplace: API cleanup
Implements #47
Fix formatting
Fix docstring
SearchPanel: add style options + add corresponding constants