Some deploy script cleanup.

 - Fixed a typo
 - No need to source perlbrew / ddgc config multiple times
 - Dist is uploaded to DuckPAN with dzil, don't do it again here
Use a symink for ~/live. Rollback = change link and restart.
Don't create symlink inside ~/live if it exists
Move installation directory to ephemeral storage
Merge pull request #236 from duckduckgo/deploy-script-changes

Some deploy script cleanup.