search handler: formalized and split serveClaims

Plus a few related cleanups (better httputil use).

Change-Id: I9ea34f2fe658624d05b7a6f347f5d946759a07b5
throttle: fix crash I saw hitting reload

Change-Id: I2df79e7a2f37c44c2a8bf4f8a0968caf058ec624
uploadhelper: use a type for JSON response, not maps.

Change-Id: I642af4daf97829a813bf7dad61cc7683ec780e69
Merge branch 'master' of ssh://camlistore.org:29418/camlistore