Fixed undeclared variable.
Current state of TTL
Added functions to get back variables declared within patterns and boolean operations
Fixed bug with checking intersection, changed intersection rules to always return first type and give a warning when types are incomparable
Added special cases for void sets and lists to checking logic for transitive and transitive reflexive closure
Fixed NPE in hashcode calculation for  AbstractFunction
Added check to test framework to make sure Assert statement is enabled
Removed assert statement, since all parse methods still use this
Merge branch 'master' of github.com:cwi-swat/rascal
Moved Infrastructure to src to try to get rascal-check to compile on Jenkins
Let's not make the dependency optional
Added checks to prevent crashing maven
Added special-casing for void lists and sets to type checking rules for lrel and rel composition
Merge branch 'master' of github.com:cwi-swat/rascal
Merge branches 'master' and 'refactor-subtype' of https://github.com/cwi-swat/rascal into refactor-subtype
Small fix after merge with master.