added Flex.scan_all
moved the nil data support for post and put in patron
added support for model migration
added :stop_indexing_proc reserved variable
updated support for migrations
flex/tasks always loaded
migration > live_reindex refactoring
changed behaviour for :live_reindex opt
Revert "added :stop_indexing_proc reserved variable"

This reverts commit b58dad2797e17e31920a185bd3dc20e4c6cd8be4.
updated support for new LiveReindex
refactoring to support the live-reindex