Remove hand-written .gir files, move PEP-8 inquisition into top Makefile.am

Remove hand-written .gir files, move PEP-8 inquisition into top Makefile.am

We have more comprehensive testing in tests/scanner and tests/everything,
and these tests were designed from a time when we were trying to make
the g-ir-generate output exactly match the .gir, which has not been true
for some time and will not be in the future.