Add Documentation for Saving all annotations to Server

[abhilashsajeev]

In Real world case it would be better to set initial annotations property and also save annotation data to server api

[taoky]

OK, I will try to carry out a better documentation after I have finished my final exams.

[taoky]

Hi,

I have read these code today and I think that saving all annotations can be done by:

• Implement a StoreAdapter that connects to your server, or
• Use LocalStoreAdapter to store annotations first in localstorage, and then save these annotations to server regularly.

And I have to remind that even with some bugs fixed compared with upstream (Submitty) version, the code quality is still not production-ready and it's recommended to use it only for prototype.