Incorporates the following:

- migrates back small change to gems:build:force from bfc1609a to finish closing #2266.

- unrolls to_proc calls in gems.rake, to match the change in master.

- fixes #2722 by passing the options hash to dependencies during build. (includes a test)

- fixes #2721 by loading the specification directly in from_directory_name. Adds an option to opt-out of specification loading when needed (in gems:refresh_specs, for instance). Includes tests.

- fixes #2679 by refreshing specs for all frozen gems rather than just gems loaded from the environment.

- fixes #2678 by passing the options hash to dependencies during unpack.

Signed-off-by: Michael Koziarski <michael@koziarski.com>