Added equality and hashCode to the ConstantKeywordParameterInitializer

related to improving cwi-swat/rascal#621
Added toString in case of printing a initializer
Fixed hashCode for constructor type
fixed bug in equals of ConstructorType, due to java.util.HashMap not implementing equals()
fixed pom with new github uri
Made the maximal sharing compression optional

(related to issue rascal#97 and #40 )
Added "timed outable" locks around the non-thread-safe LRU caches

The timeouts are to "prevent" deadlocks
removed defaults feature
one bug with missing keyword param and equals, and layout fixes
fixed a bug
Writing values of external type with the BinaryWriter now throws an exception, versus doing nothing and causing an error on read
indent
fixed bug in binary writer
fixed a bug
removed defaults feature
one bug with missing keyword param and equals, and layout fixes
fixed a bug
indent
fixed bug in binary writer
fixed a bug