Support "All Permissions" to Sandalphon Partners

[prabowo02]

It's a bit inconvenient to tick all those permissions everytime a new partner need to be added.

Usually one contest may consists of > 5 problems, and there may be about 4-5 people involved with the problemset, which results in about 5510=250 manual ticking operations

Possible solution is to either:

• On adding new partner, all permissions are checked by default
• Add a "all permissions" button (just like Contest Supervisors)

[fushar]

Maybe we can do the following:

• Supporting adding multiple partners at once (comma-separated), and
• All permissions are checked by default

[fushar]

The above have been implemented in Judgels v2!