0.1 alpha 4

Milestone with issues list - Maven - Javadoc

*new* heap analyses: type-based and point-based
*new* code location interface instead of source file coordinates
*new* type-conversion symbolic expression
*new* abstract domains can express what they track
*bugfix* string representation is deterministic for collection-based domains
*bugfix* improvements and testing of type inference
*bugfix* improvements of call target resolution