[rackspace] updated getting_started.md to use source 'https://rubygems.org' rather than :rubygems.
[rackspace|compute_v2] added bootstrap and ssh section to compute documentation.
mend
[rackspace] tweaking getting started page
[rackspace] adding note about credentials in the getting started document
[rackspace] revising getting started page
[rackspace|compute_v2] updated the bootstrap section of the compute_v2 documentation.
Merge pull request #1718 from rackspace/boot_doc

[Rackspace] Revising Getting Started Documents