Client side remote filesystem Support

Added File side support for remote filesystem:

• Anytime remote filesystem cannot be reached, local file store is used instead
• notes are zipped and uploaded on every save
• Newer zip file is used (between remote and local)
• App is still usable without server

Note:

• Header for filename might change depending on server work but can be addressed in future PR

Work Left till future PR:

• Saving creation date in each note's filename