Improve information message about rebuilding the index

When initialising Gerrit into an existing workspace, the index
should be "rebuilt", not "built".  Change the message accordingly.

Also add a new line at the beginning of the message to make it
stand out from the other information that is being output.  This
is consistent with other warnings such as the warning about
bouncycastle not being bundled.

Change-Id: I2ef5b9e141097da70fafd9dcf266988e9d6aaa27
1 file changed