[embed-rake-task] Setup rake task outside of rake dsl

I am hoping to declare this simple task programmatically, rather than
expecting rake (or configuring rake) in a dependent project to consume
this .rake file with the Rake DSL in mind.
[embed-rake-task] Move 'to-web' rake task to library

* Must now be required in if you want to see 'rake to-web' run locally

* Should also now be present for any hosting project that requires
  'rake-to-web'
Gemspec Update
Merge pull request #3 from jedcn/embed-rake-task

Add 'to-web' as a rake task for dependent projects