Spirit: applying patch improving assert messages, fixing a couple of lexer problems caused by recent changes, added target state to token definition syntax, allowing semantic actions to be attached to lex::char_() and lex::string()

[SVN r66795]

libs/spirit

@@ -1 +1 @@
-Subproject commit c905a5110096531166aaf77fb13efb556d4c1d46
+Subproject commit e23732602a2e70915cc4f0cea86f0e72a76afd34