using filesystem api to save file to the sandboxed storage:
1. saving the file directly from the filesystem
2. checking whether the file exist already in the filesystem when entering a swarm (resume)
//TODO: support fail to allocate quota, and allocate quota dynamically according to file size
#45: each slice of the file loaded wait for it to be written to filesystem and then continue with the next slice
#46: Checks the user's filesystem quotas accroding to file size and only if available uses the filesystem
added apiValidator for filesystem
#44: progress bar for loading the file added
#40: reseed and resume works if previously used filesystem

Changed block size
Merge branch 'master' of https://github.com/Peer5/ShareFest

Conflicts:
	core/util/namespaces.js
	sharefest/clientConfig.js
	sharefest/public/js/sfClient.js
	sharefest/run-prod.sh
	sharefest/server.js
	sharefest/server/lib/client-includes.js
	sharefest/server/lib/router.js