Refactor build console code, prepare to use prefs.
Added preference page to customize build console colors.
Made build console react to color pref changes immediatly.
Added ACTIVATE_ON_ERROR_MESSAGES console option
Initial refactoring of some preferences code.
More refactoring of preferences code.
Refactoring of melnorme.lang.ide.core.utils.prefs
Move prefs class.
Refactoring of Go workspace and env related code.
Rename console package and some classes.