Remove unnecessary logback-test.groovy

Remove: Since logback does not provide support for a logback-test.groovy, the file is not necessary.
New logging pattern

Add: Since logback takes most time resolving the file name and line number where a log record has been sent, a new logging format is now used.
Rename "graphics-update" thread to just "graphics"

Add: The graphical update thread is now called just "graphics" instead of "graphics-update".
Rename GraphicsThread and own TickThread file

Fix: The old graphical UpdateThread is now called GraphicsThread.
Add: The TickThread class now has its own file.
Remove graphic and tick thread access

Remove: Users of the GraphicsManager or Ticker can no longer access the backing threads.
Performance: Ticker caches unmodifiable tick action list

Add: The Ticker class caches an unmodifiable instance of the tick actions, so accessing Ticker.getActions() should be much faster now (that method is used by the tick thread every tick).
General javadoc improvements

Fix: Some small javadoc issues.
FileAddAction.IS_EXECUTABLE_BY does not check for invalid paths

Remove: The IS_EXECUTABLE_BY implementation of FileAddAction does no longer check for invalid paths since the actual EXECUTE function takes that responsibility.
Fix ParentFile.CHILDREN.add() size check

Fix: The ParentFile.CHILDREN collection property now correctly checks whether there is enough space for a new child file to be added.
Add more FileCreateProgram error events and javadoc

Add: FileCreateProgram can now fire more events when different errors occur.
Add: Javadoc to the FileCreateProgram class and all subclasses.
Update logback

Note: Now using the latest version of logback-classic (1.1.2).