Lemoncheesecake

- **API**: Change `*_that_entry` API by passing actual in a 'in_' parameter and add
a Context Manager named `this_dict` that helps passing the actual value to those functions
- **HTML report**: Fix handling of tests being executed at the time of html report rendering

- Add `log_url` function that logs URLs into the report
- Add `is_bool` matcher
- Rename `is_not` matcher into `not_`
- Fix encoding issue when match result description is unicode

- Fix crash when using the SAVE_AT_EACH_EVENT report saving mode (JSON & XML)
- Add support for smarter key lookup in imbricated dicts in *has_entry* matcher

- Support UserError exception as a 'special' exception when loading testsuites (UserError can now be used for
example while generating dynamically a testsuite to display an error message to the user)

- **matchers**: add the following new matchers: *something*, *existing*, *is_in*, *is_between*
- **matchers**: add a constant *DISPLAY_DETAILS_WHEN_EQUAL* in *lemoncheesecake.matching* that can be used to hide matchers details when the actual value is equal to the expected value
- **matchers**: fix various matcher description wording issues
- **packaging**: set additional metadata information in setuptools

- **API**: introduce new lemoncheesecake.matching API
- **API**: replace test outcome by test status