schema: add FileTime to guess the file
creation time from potential file metadata.
camput: add the -exiftime option that allows
the use of the above for -filenodes and -vivify.

Fixes: http://code.google.com/p/camlistore/issues/detail?id=77

Change-Id: I05d1af3d875bb984e47e06775fd149e5ed0ed7b1
appengine: don't build contextpool except in appengine context
serverconfig: make the localdisk optional, so that
s3 can be used as the primary blobserver.

Fixes http://code.google.com/p/camlistore/issues/detail?id=81

Change-Id: I12a7eb9a3dafc885eaaf14ba8da8716a6440416a
Merge "serverconfig: make the localdisk optional, so that s3 can be used as the primary blobserver."
Make sqlite support optional and detectable.
Merge branch 'master' of ssh://camlistore.org:29418/camlistore
Merge "schema: add FileTime to guess the file creation time from potential file metadata. camput: add the -exiftime option that allows the use of the above for -filenodes and -vivify."
serverconfig: sqlite support and general cleanups.
Merge branch 'master' of ssh://camlistore.org:29418/camlistore
camlistored: much better sqlite support, by default, and help/docs/hints