Log message:
* Use lang/ruby/gem.mk instead of misc/rubygems/rubygem.mk.
* Remove default value of GEM_BUILD.

Log message:
Import ruby-soauth-0.2 as security/ruby-soauth.

## The "S" is for "Signs" ##

*SOAuth* is a Ruby library that **creates HTTP headers for OAuth Authorization**
using previously-obtained OAuth keys/secrets.  Useful if you want to make your
own HTTP request objects instead of using the ones created for you using the
[commonly-used OAuth gem](security/ruby-oauth).

It should be noted that this was developed without edge cases in mind -- it was
pretty much abstracted from my "by-hand" signing of OAuth requests in [Prey
Fetcher](http://preyfetcher.com), so don't consider it production-quality code
(though it [is running in production](http://preyfetcher.com)).