Faster CRC32C and fix some permissions

chmod -x util/auto_roll_logger_test.cc

Maybe my C++ is a bit rusty, but it seems like this should work:

crc32c: choose function in static initialization
Before: 4.430 micros/op 225732 ops/sec; 881.8 MB/s (4K per op)
After: 4.125 micros/op 242425 ops/sec; 947.0 MB/s (4K per op)