Enabling the "skip_natural_keys_validation" data provider setting,
the natural keys for REST API/Web Admin as usernames, admin names,
folder names are not restricted to unreserved URI chars
Fixes#334#308
- add JWT authentication
- admins are now stored inside the data provider
- admin access can be restricted based on the source IP: both proxy
header and connection IP are checked
- deprecate REST API CLI: it is not relevant anymore
Some other changes to the REST API can still happen before releasing
SFTPGo 2.0.0
Fixes#197