basic metadata implemented for nimbus client v2
implemented basic metadata file class
DataBlock and EncDecProvider classes implemented
base implementation of TransactionsManager and SmartFileObject
locks implemented for Transaction, TransactionsManager and DataBlock
basic Journal class implemented
reincarnated tests/client_base_test.py
improved transactions manager for log restoration
fixed transactions manager for failed download transaction
fixed transactions failures issues
implemented Journal sync thread
refactored encdec_provider
data block appending implemented
remove M2Crypto from dependency
fixed idepositbox client for new nimbus client core
smart file object seek implemented
fixed journal, smart_file_object and metadata_file
fixed moving filesystem objects
fixed restoring metadata from journal
support of empty files and files rewrite for NimbusFS