Add get-about-memory script.

This script triggers about:memory dumps from all running Gecko processes, then pulls them off the device.
store all device manifests on the same branch
fix broken unagi syncing
Rename get-about-memory to get-about-memory.py.
Merge pull request #112 from jlebar/get-about-memory

Add get-about-memory script.
Initial mochitest frontend support in test.sh

Depends on https://bugzilla.mozilla.org/show_bug.cgi?id=797154
Merge pull request #134 from marshall/mochitest

Initial mochitest frontend support in test.sh
Arg passing fixes for test.sh and marionette
Update gitignore.
Include the output of b2g-procrank and b2g-ps in our about:memory dump.
In get-about-memory.py, get procrank in addition to b2g-procrank, because vanilla procrank has |free| info at the bottom.
In get-about-memory.py, merge the memory reports into one big file (keep the small files, too).
Fix up get-about-memory.py's import list to conform with PEP 8.
Fix dict.keys() comparison in get-about-memory.py.
Merge pull request #137 from jlebar/get-about-memory

Various improvements to get-about-memory.py script
Merge pull request #136 from jlebar/gitignore

Update gitignore.
build.sh should drive blob setup
Merge remote-tracking branch 'origin/master' into build-does-firmware
fix error in config.sh
fix typo (chagned -> changed)