Fix Bls12-377 scalar group generator

[alex-ozdemir]

Previously we used 11 as a generator, which has order (p-1)/35.

Now we use 22, which has the right order.

Fixed the two-adic root of unity in accordance with the new generator.

fixes #57

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[alex-ozdemir]

I guess that tests would have to go in the test template crate.