Add quiet switch. Convert most output to logging

[reedstrm]

As is, dbmigrator is a bit chatty. Move most output to logger.info, and add a quiet switch. I will take advantage of this in cnx-db/script/ci_test_migrations.sh to make non-CI invocation almost completely silent, so migration failures stand out.

[reedstrm]

Hmm, I broke all the tests. Code works, though :/

[karenc]

:laughing: No problems. I'll fix them later. It's something I thought about doing.

[reedstrm]

I was going to recommend to Sisi that she be sure to run script/ci_test_migrations.sh, but then I realized it's massively unreadable output - great for CI, bad for human.

[reedstrm]

BTW, here's the commit I use this in: https://github.com/Connexions/cnx-db/pull/88/commits/38d06ac04364bdc5311357d86d28c426b1d1cee4

[coveralls]

Coverage decreased (-0.2%) to 96.911% when pulling d204d0478fde6ef4356e8875ed0a0563592abe87 on Connexions:quiet-and-log into 63e6329eec71cb42b1ebe75206af72d38a33e3b6 on karenc:master.

[coveralls]

Coverage increased (+0.5%) to 97.633% when pulling c14b0bff145190adaa675c297affe610846c97c0 on Connexions:quiet-and-log into 63e6329eec71cb42b1ebe75206af72d38a33e3b6 on karenc:master.

[coveralls]

Coverage decreased (-0.03%) to 97.115% when pulling 46ce7a8de6f55e28e07a9bea5d38ff3c2de003f1 on Connexions:quiet-and-log into 63e6329eec71cb42b1ebe75206af72d38a33e3b6 on karenc:master.

[coveralls]

Coverage increased (+0.5%) to 97.633% when pulling 576a6be65a84ddab1343432068bb3898a520f267 on Connexions:quiet-and-log into 63e6329eec71cb42b1ebe75206af72d38a33e3b6 on karenc:master.

[coveralls]

Coverage increased (+0.5%) to 97.633% when pulling 576a6be65a84ddab1343432068bb3898a520f267 on Connexions:quiet-and-log into 63e6329eec71cb42b1ebe75206af72d38a33e3b6 on karenc:master.