cleaning up and condensing ligoauth migrations

ligoauth/migrations/0001_initial.py

ligoauth/migrations/0002_auto_20150708_1134.py

...auth/migrations/0002_set_ligoauth_ligoldapuser_charset.py

ligoauth/migrations/0003_auto_20150819_1201.py

...th/migrations/0003_initial_localuser_and_x509cert_data.py

ligoauth/migrations/0004_add_grdinj.py

ligoauth/migrations/0005_add_robot_grdinj.py

ligoauth/migrations/0006_readd_gstlalcbc_test.py

ligoauth/migrations/0007_add_pycbclive_robot.py

ligoauth/migrations/0008_add_exttrig.py

ligoauth/migrations/0009_add_pankow_robot_and_cert.py

...auth/migrations/0010_add_nagios_gracedb_robot_and_cert.py

ligoauth/migrations/0011_add_O2_hwinj_logger_account.py

ligoauth/migrations/0012_update_iDQ_robot.py

ligoauth/migrations/0013_update_bayeswave_robot.py

ligoauth/migrations/0014_update_lib_robot.py

ligoauth/migrations/0015_update_bayestar_robot.py

ligoauth/migrations/0016_add_losc_account.py

ligoauth/migrations/0017_add_virgo_detchar.py

ligoauth/migrations/0018_update_lib_accounts.py