Renamed last remaining GUI occurences to be named Gui.
Modified .gitignore file to ignore *.VisualState.xml from NUnit.
Moved update-version.sh script to subdirectory util.
Renamed subdirectory util to .util to indicate that the contents should only
be used by maintainers.
Logging.Target.File.logMessage no longer adds a new line at the end of the message.
Changed Logging.Target.IBase.logMessage to Logging.Target.IBase.write with same signature.
Logging.Manager now implements the new interface Logging.IManager.
This new interface defined write, writef, writeln, and writefln methods.
The static property Manager.Instance is now of type IManager and has a public setter.
Merge branch 'interface-change-logging-target-base' into development