send the static_generator_{init, finalized} signals.

Note: The two signals were already present but were never sent.
use correct CachingGenerator class in super() call

This was a leftover from code moving in c1324b0.
Detected by pylint.
Merge pull request #1329 from smartass101/fix_caching_subclass_super

use correct CachingGenerator class in super() call
Merge pull request #1328 from Scheirle/StaticGeneratorSignals

Send the static_generator_{init, finalized} signals