LIVEOAK-73 Provide file upload / download endpoint using Mongo GridFS as storage

A new module mongo-gridfs is an implementation of a REST endpoint for uploading, and downloading large files which are stored in a MongoDB instance.

To support the ability to not load entire HTTP bodies into memory several changes had to be made to container module.
 - Netty channel auto-read has been turned off for precise control of receiving read events.
 - HttpRequestBodyHandler has been introduced which handles HTTP body upload
 - changes have been made to support lazy body read by BinaryResources having to explicitly express interest in body
 - resource state is always an instance of LazyResourceState when going through complete pipeline via http

Some of TODOs, and possible TODOs:
 - download still loads a whole body into memory due to MyBinaryContentSink
 - further cleanup needed of ResourceState, and BinaryResource, and upload / download handling
 - updating existing blob resource
 - updating just metadata
 - additional file and directory metainfo
 - partial uploads / downloads to continue interrupted operations
 - transfer encoding to reduce size
 - multiconnection upload / download in conjunction with partial upload / download for better bandwidth utilization