Prioritize the last commit in a pull request
Prioritize the last commit in a pull request

Prioritize the last commit in a pull request or
recent mergings into master over other builds.
Parse out the part and total from the Pull-request
line in commit messages, if part is equal to total
then prioritize that build over others.

Reviewed-by: Håkan Johansson <15489a8f6a48d6279c06f8d0aa9dfd8c8750ff60@chalmers.se>
Reviewed-by: Brian Behlendorf <32d50ad1e384dcb9a5bf7e40fa470df5dabaf348@llnl.gov>
Signed-off-by: Giuseppe Di Natale <8f90fd86203578c7bda52281540dd9a2276d6d80@llnl.gov>
Closes #40

gmelikov/zfs-buildbot,gmelikov/zfs-buildbot,zfsonlinux/zfs-buildbot,zfsonlinux/zfs-buildbot