Better reviews for the same cost in gcc-linaro

[Michael Hope]

We currently use a feature branch / merge request / merge / test /
push approach in gcc-linaro.  This works fine for a reasonable cost
but can mean that patches sit unreviewed and unmerged for up to a
month.  Ramana, Andrew, and I had a talk about this earlier in the
week and I've written up the ideas here:
  https://wiki.linaro.org/MichaelHope/Sandbox/ReviewThoughts

We're a bit unique as gcc-linaro started from a mature base, running
the testsuite takes days, and the product is so big that bzr takes a
long time to work on it.

If you have experience in running a master branch or ideas on
continious integration please have a read.

-- Michael