Using `#constructor' in place of `#__construct' caused an error attempting
to "redefine" `#__constructor' (once the alias was applied); the system was
making improper assumptions and not accounting for aliases.
In fact, everthing about how this was being done was bad, since adding any
keywords would have thrown it off as well!
* lib/ClassBuilder.js (build): Move ector detection past prop
parsing. Check parsed properties instead of raw.
* test/ClassBuilder/ErrorExtendTest.js: Iterate ctor override test on new
`ctors'.
(caseSetUp) [ctors]: Add property.