Seafile remote support

[sgaduuw]

Pre-Submission checklist

• [x] There is no existing issue that already asks for this feature.
  
• [x] The feature already exists in rclone (on your PC or in Termux)
• [x] I am prepared to help make this feature, but Java makes no sense to me at all.

What version of RCX are you using (About -> App version)?

1.12.2

What problem are you trying to solve?

I make regular use of the non android rclone tool, which has support for Seafile remotes. Could Seafile be added to configurable remotes in RCX as well, please?

What should RCX be able to do differently to help with this problem?

Add SeafileConfig.java in 'app/src/main/java/ca/pkay/rcloneexplorer/RemoteConfig/SeafileConfig.java', run around naked in the forest during a full moon, chanting 'Java, Java, Java' at least 3 hours long. Expand the switch in 'app/src/main/java/ca/pkay/rcloneexplorer/RemoteConfig/RemoteConfig.java' with a case for SEAFILE Expand provider_ids in 'app/src/main/res/values/arrays.xml' with SEAFILE Probably something else, but nothing i can deduct from Github search

[fungs]

Any change to get this going? Maybe, if we get a description of todos to make this happen, someone can step in and curate a PR for it?