BibSched: fix monitor

BibSched is currently _borken_. Here is an attempt to fix it.

Before:
---------
* Running any task or going to auto mode gets an exception due to missing config variable.
* Running any task after above fix reveals wrong datetime calls.
* Fixing all of the above revealed wrong lookup of `Task` class.

After:
---------
It works :tm: 

1: D100 Docstring missing
41:1: F401 'CFG_INSPIRE_SITE' imported but unused
75: D400 First line should end with '.', not 'h'
75: D205 Blank line missing between one-line summary and description
96: D400 First line should end with '.', not 'm'
96: D205 Blank line missing between one-line summary and description
131: D200 One-line docstring should not occupy 3 lines
137:9: F821 undefined name 'cfg'
146: D200 One-line docstring should not occupy 3 lines
152:9: F821 undefined name 'CFG_BIBSCHED_EDITOR'
163: D101 Docstring missing
167: D401 First line should be imperative: 'Return', not 'Returns'
167: D209 Put multi-line docstring closing quotes on separate line
167: D205 Blank line missing between one-line summary and description
167: D208 Docstring is over-indented
189: D103 Docstring missing
202: D400 First line should end with '.', not 'd'
217:1: E302 expected 2 blank lines, found 1
221:1: E302 expected 2 blank lines, found 1
221: D400 First line should end with '.', not ')'
228: D401 First line should be imperative: 'Return', not 'Returns'
237: D401 First line should be imperative: 'Return', not 'Returns'
246:68: E261 at least two spaces before inline comment
266:45: E127 continuation line over-indented for visual indent
277:45: E127 continuation line over-indented for visual indent
280: D400 First line should end with '.', not 't'
280: D205 Blank line missing between one-line summary and description
296: D400 First line should end with '.', not 'k'
334:1: E302 expected 2 blank lines, found 1
338:1: E302 expected 2 blank lines, found 1
362: D103 Docstring missing
366:1: E302 expected 2 blank lines, found 1
366: D103 Docstring missing
371: D103 Docstring missing
376: D103 Docstring missing
387: D101 Docstring missing
388: D102 Docstring missing
398: D102 Docstring missing
401: D102 Docstring missing
404: D102 Docstring missing
407: D102 Docstring missing
413: D102 Docstring missing
416: D102 Docstring missing
420: D101 Docstring missing
421: D102 Docstring missing
439: D401 First line should be imperative: 'Set', not 'Sets'
439: D400 First line should end with '.', not 't'
439: D205 Blank line missing between one-line summary and description
446:45: E127 continuation line over-indented for visual indent
449: D401 First line should be imperative: 'Remove', not 'Removes'
449: D202 No blank lines allowed *after* method docstring, found 1
449: D400 First line should end with '.', not 'e'
449: D200 One-line docstring should not occupy 2 lines
465: D209 Put multi-line docstring closing quotes on separate line
465: D400 First line should end with '.', not 'n'
465: D205 Blank line missing between one-line summary and description
480: D102 Docstring missing
483:41: E127 continuation line over-indented for visual indent
485:41: E127 continuation line over-indented for visual indent
489: D400 First line should end with '.', not 't'
489: D205 Blank line missing between one-line summary and description
499:22: E126 continuation line over-indented for hanging indent
524:9: E303 too many blank lines (2)
532: D209 Put multi-line docstring closing quotes on separate line
532: D400 First line should end with '.', not 'd'
532: D205 Blank line missing between one-line summary and description
546: D209 Put multi-line docstring closing quotes on separate line
546: D205 Blank line missing between one-line summary and description
756: D102 Docstring missing
834:13: E128 continuation line under-indented for visual indent
835:57: E126 continuation line over-indented for hanging indent
846: D400 First line should end with '.', not 'e'
872: D102 Docstring missing
880:34: E127 continuation line over-indented for visual indent
883: D102 Docstring missing
892: D102 Docstring missing
905:58: E127 continuation line over-indented for visual indent
930: D102 Docstring missing
967: D103 Docstring missing
977: D401 First line should be imperative: 'Thi', not 'This'
977: D300 Expected """-quotes, got '-quotes
986: D103 Docstring missing
991: D401 First line should be imperative: 'Print', not 'Prints'
1034: D103 Docstring missing
1039: D103 Docstring missing
1043: D103 Docstring missing
1061:12: E713 test for membership should be 'not in'
1068: D103 Docstring missing
1072: D209 Put multi-line docstring closing quotes on separate line
1072: D202 No blank lines allowed *after* function docstring, found 1
1072: D400 First line should end with '.', not 'g'
1072: D205 Blank line missing between one-line summary and description
1126:49: E261 at least two spaces before inline comment
1126: D103 Docstring missing
1147:48: E261 at least two spaces before inline comment
1147: D209 Put multi-line docstring closing quotes on separate line
1147: D205 Blank line missing between one-line summary and description
1155:17: E128 continuation line under-indented for visual indent
1165:76: E261 at least two spaces before inline comment
1165: D202 No blank lines allowed *after* function docstring, found 1
1165: D200 One-line docstring should not occupy 3 lines
1170: D200 One-line docstring should not occupy 3 lines
1192:29: E126 continuation line over-indented for hanging indent
1193:42: E203 whitespace before ':'
1194:21: E128 continuation line under-indented for visual indent
1225: D103 Docstring missing
1230: D400 First line should end with '.', not 'd'
1230: D205 Blank line missing between one-line summary and description
1274: D103 Docstring missing
1325:22: E203 whitespace before ':'
1326:15: E127 continuation line over-indented for visual indent
1326:22: E203 whitespace before ':'
1329:13: E128 continuation line under-indented for visual indent
1330:13: E128 continuation line under-indented for visual indent
1331:13: E128 continuation line under-indented for visual indent
1332:13: E128 continuation line under-indented for visual indent