Add h2 tag to improve aesthetics
update for stage 2
update copy
link doc and add Freddie Mercury
clarify local repo language
Merge pull request #197 from c4hrva/gach-stage-2

Gach stage 2
Update README.md

elaborate purpose
add org board & reorganize sections
trim words
Merge branch 'master' of https://github.com/codeforamerica/brigade
Merge branch 'master' of git://github.com/codeforamerica/brigade