new feature: token mode

support setup token mode:

• no require token
• require medium level token
• require high level token

2.0.1-beta: fix:defer process when streaming file got error (#13)

Fix: handle when streaming to server got error
Note: Main version with simple token, no validate token with specify path

Support user account

Support user account
Preload lock

Expose API verify token for integrate with third party

Merge pull request #4 from handl3r/feature-expose-auth-api

Add verify api

Deep search on Google Drive file system

Fix any case file name include with ' can search and download