re-apply changes to broker errors section
Merge pull request #248 from stupakov/broker-error-documentation-2

re-apply changes to broker errors section
re-apply misc changes that have since been overwritten by merging of PRs
clarify difference between the two ruby example brokers
Merge pull request #249 from programsam/master

Better documentation for testing out cinder volumes
Merge pull request #250 from stupakov/service-brokers

re-apply more misc changes that have since been overwritten by merging of PRs
change the title in the api pages

fix a link
put the change log in chronological order.
Merge pull request #251 from stupakov/api-page-title-change

change the title in the api pages