Render preview as Mongo-style JSON array instead of print_r.
Merge branch 'master' into jsonpreview

Conflicts:
	mongodbadmin.php
Merge remote-tracking branch 'jwage/master' into jsonpreview
Merge branch 'master' into jsonpreview
only collapse onto a single line if it's not already a collapsed list or hash.
Merge remote-tracking branch 'bobthecow/jsonpreview'

Conflicts:
	mongodbadmin.php