Add push option to skip rules validation

Validation rules may block commits that should be uploaded regardless of
the rules (e.g. false positives, exceptions, etc).

This patch provides Gerrit administrators ability to allow their
uploaders to bypass all validation rules by using git push option
"uploadvalidator~skip". This feature is controlled by uploadvalidator
config "skipViaPushOption".

Bug: Issue: 14362
Change-Id: I4305ea8a0923e531742ee77d8bd9d394099e2eb9
21 files changed