add --exclude-config to opt out of 1 or more configs. This always is respected,

add --exclude-config to opt out of 1 or more configs. This always is respected,
regardless of the ordering of --config and --exclude-config.

add --verbose [-v] to dump extra info, e.g. what configs are being run

changed --config to enforce a unique set of configs to be run, such that
--config 8888 --config 8888 results in just 1 run of 8888.
Committed: https://code.google.com/p/skia/source/detail?r=7013

[bsalomon, 2013-01-04 14:33:00]

On 2013/01/04 14:31:09, reed1 wrote:

LGTM

[EricB, 2013-01-04 14:35:13]

LGTM