renamed getCanonicalSignature added externalTypes instead of types for interface functions added simple test
renamed getCanonicalSignature
added externalTypes instead of types for interface functions
added simple test

todo
testing

chriseth/mix,LefterisJP/mix,LefterisJP/mix,yann300/mix,LefterisJP/mix,ethereum/mix,ethereum/mix,yann300/mix,vaporry/mix,tomthebuzz/mix,chriseth/mix,LianaHus/mix,vaporry/mix,ethereum/mix,LianaHus/mix,LianaHus/mix,yann300/mix,vaporry/mix,tomthebuzz/mix,chriseth/mix,tomthebuzz/mix