Add CheckMilestone command

This determines PRs between a range and
then checks whether or not they have a
milestone set.
Suggested improvements from Sebastien

 * Catch 404 on invalid permissions
 * Include PR in message
merge master -D org -I include -E conflict -E needs-fixes -E broken: PR 43 (Add CheckMilestone command)
merge master -D org -I include -E conflict -E needs-fixes -E broken: PR 46 (Fail-fast if bad credentials are used)
merge master -D org -I include -E conflict -E needs-fixes -E broken: PR 47 (Auto submod updating)
merge master -D org -I include -E conflict -E needs-fixes -E broken

Repository: openmicroscopy/snoopycrimecop
Already up-to-date.
Merged PRs:
  # PR 43 joshmoore 'Add CheckMilestone command'
  # PR 46 sbesson 'Fail-fast if bad credentials are used'
  # PR 47 joshmoore 'Auto submod updating'

Generated by SCC-merge#114 (http://hudson.openmicroscopy.org.uk/job/SCC-merge/114/)