Convert scripts to entry_points

This MR converts all of the scripts previously managed in bin/ into entry points constructed from code now managed as modules in the new dqsegdb.tools subpackage.

Using entry points rather than scripts has a few advantages

• much easier to test functions in the code independently of the whole
• much easier to measure coverage
• entry points are more portable (easier to install on non-Unix platforms, for example)
• allows for a noarch: python conda package (niche benefit)

This should have no impact on the functionality or usability of any of the current scripts.

dqsegdb/tools/ligolw_segment_insert.py

@@ -81,8 +81,6 @@ __author__ = "Ryan Fisher <ryan.fisher@ligo.org>"
 __version__ = get_versions()['version']
 __id__ = get_versions()['full-revisionid']
 __date__ = get_versions()['date']
-__verbose_msg__ = "version: " + get_versions()['version'] + "\nfull-revisionid: " + get_versions()['full-revisionid'] + "\ndirty: " + str(get_versions()['dirty']) \
-    + "\nerror: " + str(get_versions()['error']) + "\ndate: " + get_versions()['date']
 __formatted_date__ = __date__[0:10] + " " + __date__[11:19] + " +0000"
 #__formatted_date__ = __date__[0:10] + " " + __date__[11:19] + " " + __date__[19:25]   # it would be nice to fix this so that the time isn't off by a few hours
 #__src__ = git_version.status