-ensures signals and signal classes are unmapped properly as remapping a previously unmapped signalClass was failing
-updated tests targets.hxml to include -lib mdata
-fix failed to consider mapping two commands to the same SignalClass then unmapping one
-new test fails and needs to be addressed
Only remove signal instance and unmap injector if there are no other mappings
for the signal class. (ie one signal class mapped to multiple commands).
Add test to ensure unmapping of command from command map means it will not be executed in future.
Merge pull request #6 from massiveinteractive/hotfix/unmap-signal

Hotfix/unmap signal