Merge of 'ayardley/parrot_github_release'

[Alvis Yardley]

Hello all:

I would like to merge 'ayardley/parrot_github_release' if there are no
objections. 

The branch,

1. adds 'tools/release/parrot_github_release.pl', which does two things:

   a. packages the 'parrot.github.com' repository and 

   b. archives the previous documentation release into the appropriate,
   supporting 'parrot-docsx' repository;

2. updates Section X of 'docs/project/release_manager_guide.pod' to reflect
the inclusion of the tool; and 

3. updates 'docs/project/release_parrot_github_guide.pod', also, to reflect
the inclusion of the tool. 

It also closes issue #6 of parrot/parrot.github.com, if the production runs
correctly that is.

I look forward to your comments and suggestions.

Thank you. 
-- 
Alvis