added 'true', and 'false' as keywords in lexer.
added 'true', and 'false' as keywords in lexer.

jckarter/clay,mario-campos/clay,mario-campos/clay,jckarter/clay,iamrekcah/clay,aep/clay,aep/clay,iamrekcah/clay,mario-campos/clay,iamrekcah/clay,aep/clay,aep/clay,jckarter/clay,aep/clay,mario-campos/clay,iamrekcah/clay,jckarter/clay,jckarter/clay,iamrekcah/clay,jckarter/clay,aep/clay,mario-campos/clay