Mloggers

Fixed a bug where serialization of message objects would modify the original object via reference.

**Full Changelog**: https://github.com/serhez/mloggers/compare/1.3.2...1.3.3

Thorough attempts to JSON-serialize objects in the `FileLogger`.

**Full Changelog**: https://github.com/serhez/mloggers/compare/1.3.1...1.3.2

Lists and `numpy` arrays are now properly supported as messages (or as values within a dictionary).

**Full Changelog**: https://github.com/serhez/mloggers/compare/1.3.0...1.3.1

Breaking changes

- `set_level` is now `set_min_priority`.
- The `default_level` argument in the `Logger.__init__` method is now called `default_priority`.

**Full Changelog**: https://github.com/serhez/mloggers/compare/1.2.1...1.3.0

New `OptionalLogger`, read the README for more.

**Full Changelog**: https://github.com/serhez/mloggers/compare/1.2.0...1.2.1

What's Changed
* Added support for multiple arguments in logger by merlerm in https://github.com/serhez/mloggers/pull/2

Breaking changes
Since now the log function can take any number of messages, all additional parameters (like `level` or `mask`) have to be passed explicitly. For example, in the previous version the code `logger.log("message", LogLevel.WARN)` would work properly, but in this version the result would be both items get converted to strings and logged (as there is no way for the function to know where the level was supposed to be). The correct way to use the function is now only `logger.log("message", level=LogLevel.WARN)`.


**Full Changelog**: https://github.com/serhez/mloggers/compare/1.1.7...1.2.0