move source_reference to Vala.Literal, use non-null types, don't mark

move source_reference to Vala.Literal, use non-null types, don't mark

2006-06-28  Jürg Billeter  <j@bitron.ch>

	* vala/valabooleanliteral.vala, vala/valacharacterliteral.vala,
	  vala/valaintegerliteral.vala, vala/valaliteral.vala,
	  vala/valanullliteral.vala, vala/valarealliteral.vala,
	  vala/valastringliteral.vala: move source_reference to Vala.Literal,
	  use non-null types, don't mark properties as construct-only

svn path=/trunk/; revision=54