Get default register from clipboard=unnamed setting
VIM-652 Add support for executing and mapping arbitrary IDEA actions

* no tests performed..! *

Example usage:
:nnoremap gi :action GotoImplementation<CR>
:nnoremap gu :action FindUsages<CR>
:nnoremap gcw :action RenameElement<CR>

Action overview:
https://github.com/JetBrains/intellij-community/blob/6c6cb47c5a41025549157d64643a98a89481260d/platform/platform-resources-en/src/messages/ActionsBundle.properties
Implemented :findaction
Fix action execution contexts, use a delay on popup actions to allow the command handler to unwind
Renamed :findaction => :actionlist + added statusbar error message when calling invalid action names
:actionlist added support for wildcards
Extracted EditorGroup
VIM-483 VIM-410 Added support for 'number' and 'relativenumber' commands

These commands override the line numbers setting in the IDE when the
Vim emulation is enabled.
Added Jaime Sanchez to the list of contributors
Coding style
VIM-476 Added default register reset on 'clipboard' change

Added a test for :set clipboard=unnamed.
Merge branch 'clipboard-unnamed'

Conflicts:
	src/com/maddyhome/idea/vim/option/Options.java
	test/org/jetbrains/plugins/ideavim/action/CopyActionTest.java
Added 'clipboard' to the list of :set commands
Added Thomas B Homburg to the list of contributors
Updated CHANGES
Typo
Removed the list of compatible IDEs

The same list is shown on the plugin's page and duplicated in the
README.
Run the test only if the system clipboard is available
VIM-511 Fixed editing offset after <BS> for '.' command
Repeat typing commands by inserting text instead of handling a typed key

It will prevent auto-completion and other auto-inserting typed key
handlers from messing up with the repeated text.