remove symbolic backend, kagreg, kcheck, gui debugger
delete simulation (except for bare bones needed in order to test robot legs)
fix permissions on k release
incorrect file permissions last time
remove .project from k-core

we can have the external tool builder commited, but having also the .project creates one extra item to ignore manually, as it remains tracked
and ignore .project
mpfr to version 1.0.1
Merge pull request #1025 from dwightguth/assembly

fix permissions on k release
Merge pull request #1027 from cos/hotfix/remove-dot-project

remove .project from k-core
Merge pull request #1028 from cos/hotfix/mpfr_pom

mpfr to version 1.0.1
Merge pull request #1022 from dwightguth/delete-stuff

Delete stuff
reimplemented PatternExpander and Evaluator using CopyOnWriteTransformer instead of PrePostTransformer
removed some dead code
moved TruthValue to a separate class; eliminated class Implication
moved Equality & EqualityOperations to a separate class
cached the truth value of an equality since it's immutable
fixed failing tests due to non-canonicalized collection terms
more efficient Term#compareTo using hashCode
canonicalized Equality
implemented collectionVariables() as a common method for all collections