VIM-98 Invoke actions in separate commands for better Undo/Redo

Vim actions used to be invoked inside a key typing command and didn't
have their own commands. Now they've got separate commands with unique
group IDs in order to stop them from being merged into combined
Undo/Redo steps.

The Undo/Redo behaviour still differs from Vim: typing in a single
Insert mode session is split into several Undo chunks depending on
timing. An Undo step may require one more Undo step for moving the
cursor to its position before Undo.
Updated link to build server
Added forgotten release date for 0.29
Moved RegisterActions to the root IdeaVim package

This class is an entry point to nearly all Vim actions, so it should be
easier to discover.
Updated copyright years in sources
Split RegisterActions constructor into several methods
Typo
Converted a RegisterActions class instance into a function
Removed unused method
Specify size in toArray()
Fixed possible NPE
Replace StringBuffer with concatenation
Typos
Use SwingUtilities.invokeLater() for consistency
VIM-440 Fixed ':e' open file dialog
Cleanup
Cleanup
Refactored Options.loadVimrc()
VIM-425 Read config from .ideavimrc if available
Extracted VimTestCase.runExCommand()