New plugin: plugin macro

This plugin let the user record and replay some macros:
 * 3 handlers: action, find and texteditor
 * almost all texteditor and cpp actions recorded
 * options page to set the directories where the macros are stored
 * optional dialog to give a name and comment at the end of a macro
 * locator integration to play a macro
 * shortcuts assignment to macro

The most important change outside the plugin macros is the isScriptable method
for command: All scriptable commands can be stored in a macro.

Merge-request: 2176
Reviewed-by: Tobias Hunger <tobias.hunger@nokia.com>