default config added to logger; logs added for job clearing/cancelling

[zcking]

I added a default configuration for the logger, as recommended by the logging docs. I then added a logging statement to cancel_job() and clear() as well as fixed a typo in one of the existing log statements.

In cancel_job() instead of silently passing on the exception, this will log the exception and continue.

The .gitignore change is just for folks like me who use Idea IDEs such as PyCharm which creates a .idea/ folder with .iml files for some meta info the IDE uses.

---

Here is an example interactive session demonstrating the new logging:

>>> import schedule
>>> import logging
>>> schedule.logger.setLevel(logging.INFO)
>>> def job():
...     print('working...')
... 
>>> j = schedule.every(1).minutes.do(job)
>>> j2 = schedule.every(1).minutes.do(job).tag('test')
>>> j3 = schedule.every(1).minutes.do(job).tag('foo')
>>> 
>>> schedule.cancel_job(j)
2018-01-13 12:45:34,818 - INFO (schedule) - Cancelling job "Every 1 minute do job() (last run: [never], next run: 2018-01-13 12:45:59)"
>>> 
>>> schedule.clear(tag='foo')
2018-01-13 12:47:46,522 - INFO (schedule) - Deleting all jobs tagged "foo"
>>> 
>>> schedule.clear()
2018-01-13 12:47:54,916 - INFO (schedule) - Deleting *all* jobs

[coveralls]

Coverage remained the same at 100.0% when pulling 0918221 on zcking:feature/improved-logging into b4ac8ca on dbader:master.

[coveralls]

Coverage remained the same at 100.0% when pulling 0918221 on zcking:feature/improved-logging into b4ac8ca on dbader:master.

[coveralls]

Coverage remained the same at 100.0% when pulling e35d771 on zcking:feature/improved-logging into 736a6d4 on dbader:master.

[SijmenHuizenga]

Hi @zcking, thanks for the additions! Overall it looks really good. I've merged master into this branch and did some minor adjustments:

• Changed the level to debug to be in line with other log message (see Change logging level to debug #361).
• The ValueError exception only occurs if the job is not scheduled so changed the message to reflect that.

The only thing I'm not sure about is the basicConfig, let's talk about that a bit more.

[SijmenHuizenga]

Suggested change

	logging.basicConfig(
	format='%(asctime)-15s - %(levelname)s (%(name)s) - %(message)s'
	)

logging.basicConfig configures the root logger. Subsequent calls to basicConfig are ignored.

With this addition, if the schedule library is imported at the top of the file, the root logger is configured using the schedule basicConfig. Now, if the the program itself calls basicConfig to configure the root logger, that config will be ignored because it has already been configured by schedule. This is an example of such:

import logging
import schedule

logging.basicConfig(format='CUSTOMFORMAT: %(message)s', level=logging.DEBUG)

logging.info("test")

I would expect this code to print test, but with the proposed change it doesn't print anything.

This will be quite confusing for users. Therefore I'm proposing to remove this basicConfig call and merge the pr without it. Let me know what you think!

[SijmenHuizenga]

Merged master into this branch, updated the docs and removed the default logger configuration. Ready to merge 🚀