added notes to set GOROOT and GOPATH properly and go 1.1.1 should be
preinstalled.
Merge branch 'dev' into features/issue_180

Conflicts:
	docs/source/installing.rst
Doc tweaks.
More tweakage.
Merge pull request #284 from mozilla-services/features/issue_180

documentation updates to using the prebuilt binary of Go 1.1.1