Allow optional type annotations on constant declarations
Name variable lists in node grammar to prevent bug when lists are empty
Add support for inductive counterexamples (-induct_cex)
Merge branch 'master' into lustre2excel

Conflicts:
	src/jkind/ArgumentParser.java
	src/jkind/Settings.java
	src/jkind/processes/Director.java
	src/jkind/processes/InductiveProcess.java
	src/jkind/writers/ConsoleWriter.java
	src/jkind/writers/Writer.java
	src/jkind/writers/XmlWriter.java