Add reStructuredText file for PatchIncrInstallExtractCommit
Add reStructuredText file for PatchIncrInstallExtractCommit

Add a reStructuredText document for the PatchIncrInstallExtractCommit file
which explains the desired content of the JSON file and warns the user of
the Cache specific things that a user will need to be aware of.

OSEHRA-Id: http://issues.osehra.org/browse/OAT-214
Change-Id: Ib4dae304913036e8b4085cf73ff251eab8c68dd0

OSEHRA/VistA,josephsnyder/VistA,OSEHRA/VistA,OSEHRA-Sandbox/VistA,OSEHRA/VistA,shabiel/VistA,shabiel/VistA,OSEHRA-Sandbox/VistA,josephsnyder/VistA,OSEHRA/VistA,OSEHRA/VistA,OSEHRA/VistA,shabiel/VistA,OSEHRA-Sandbox/VistA,OSEHRA-Sandbox/VistA,shabiel/VistA,josephsnyder/VistA,shabiel/VistA,OSEHRA-Sandbox/VistA,shabiel/VistA,josephsnyder/VistA,josephsnyder/VistA,josephsnyder/VistA,OSEHRA-Sandbox/VistA