Caching build numbers of builds that don't exist on disk

This should reduce the amount of disk checking we are doing on the builders page dramatically

- Maxed the amount of build searching we do for the latest build on builder json
Merge branch 'staging' into katana
Merge branch 'staging' into katana
Merge branch 'staging' into katana
Merge branch 'staging' into katana
Update README file

- Remove upstream contact info so they are not bothered with undesired questions/issues.
- Make it very clear that Katana is a fork of Buildbot and provide information for
  accessing the upstream project.
- Add Katana maintainers list with contact information.
Fix formatting of README
Note that MAINTAINERS.txt may not be up-to-date at time of reading
Merge branch 'staging' into katana
Reduced the sensitivity of the animation test
Merge branch 'katana' into staging
Fixed colors for build dependencies indicator on build page