(CFACT-125) Resolve architecture fact when passed as an argument

Prior to this commit, when running `cfacter architecture` the
architecture fact would not resolve, despite the fact that it
did resolve when `cfacter` was run without any arguments.

This commit updates the POSIX processors resolver constructor to
properly include the architecture fact so it can be resolved by itself.
Merge pull request #140 from whopper/cfact-125/arch-resolution-fix

(CFACT-125) Resolve architecture fact when passed as an argument