Fixed and added spec for #info
Added docs and specs for #installed?
Fixed doc typo and puts call
Refactored, added docs and specs for #install
Fixed, added docs and specs for #remove
Added #upgrade
Removed use of cache_is_dirty
Added specs for #installed_packages
Removed #cache

Don't have a need for this right now.  Initially added it under the
understanding that #update methods updated "cache", which isn't the
case.
Added #upgrade_packages
"cache" -> "index"
Cleaned up #upgrade_pacakges spec
Nuked extra newlines
Removed unneeded stuff from #upgrade_packages specs
Updated and added specs for #update_index
Added docs for #update_index