Redefine ProcessName to allow prefixes and indices.
Merge branch 'master' into pnames
Allow for annotations and indices on process names and labels. Standard
Show instance and PrettyPrint. This brought to light bugs in that names
have been generated using show. Decorations (annotations and indices)
can be strings, variables, numbers, or variable bindings. No expansion
of decoration during convert yet.
Broke out LtsTypes. Can now print, but should make Expr also part of
Pretty.

	modified:   Data/Lts.hs
	modified:   Data/LtsPretty.hs
	new file:   Data/LtsTypes.hs
	typechange: test.lts
	modified:   ../test.lts
Added prettyExpr, and kept standard Show instance.
Uncomment and updated minimisation so that main works.
Small restructuring before merge.