Revert of depot_tools: import bot_update gclient git rietveld tryserver recipe modules (patchset #6 id:100001 of https://codereview.chromium.org/1642023002/ )

Reason for revert:
breakages: https://code.google.com/p/chromium/issues/detail?id=582229

Original issue's description:
> depot_tools: import bot_update gclient git rietveld tryserver recipe modules
> 
> BUG=582074
> 
> Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=298447

TBR=maruel@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=582074, 582229

Review URL: https://codereview.chromium.org/1644173002

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@298457 0039d316-1c4b-4281-b951-d872f2087c98