Add a test call_signatures for compiled modules

Should fail
Execute test only on 64bit platforms
Add params property to compiled object
Fix api.classes.CallDef.params

We need to check for compiled objects
Add test with standard lib

math.cos( should return <Param: x @0,0>
Fix test (bad assert)
Merge pull request #378 from ColinDuquesnoy/issue373

CompiledObject params, fixes #373