git: Make case insensitive matching nicer

Rename GrepCommits to GrepCommitsCaseInsensitive and add
--regexp-case-insensitive flag when calling git.

Change-Id: e973546cb4
Story-Id: SF-84
jira: Explain stageableStateIds

Story-Id: SF-84
Change-Id: 65430eef5b
wip [ci skip]

Change-Id: 0eae768d00
wip [ci skip]

Change-Id: 6d298b1920
wip [ci skip]

Change-Id: 6eddc1d7b0
wip [ci skip]

Change-Id: b7bff23b65
wip [ci skip]

Change-Id: 767bfe4418
wip [ci skip]

Change-Id: 0111d4deef
wip [ci skip]

Change-Id: f05a40883a
wip [ci skip]

Change-Id: d62e386f89
wip [ci skip]

Change-Id: a28d87d907
wip [ci skip]

Change-Id: a79035e4f0
wip [ci skip]

Change-Id: fc7903712e
wip [ci skip]

Change-Id: 2f705d2429
wip [ci skip]

Change-Id: 1c0c485d37
wip [ci skip]

Change-Id: 7330fa4d38
wip [ci skip]

Change-Id: 49cdc797d4
wip [ci skip]

Change-Id: 19b150985f
wip [ci skip]

Change-Id: e367f8f5a3
wip [ci skip]

Change-Id: 9c4ef678df