Cachet-client

Drop python 3.5 support.

Tags

Revamped how we interact with component tags. Previous
versions was limited to inspecting component slugs.

* ``Component.tags`` now returns a slug:name dict
* ``Component.tag_names`` returns a list of tag names
* ``Component.tag_slugs`` returns a list of slug names
* ``Components.tags`` are now read-only
* ``Components.set_tags()`` will overwrite all tags
* ``Components.add_tag`` and ``add_tags`` can be used to add tags
* All tag lookups are now case insensitive

Other Additions / Fixes

* Incidents now support the ``occurred_at`` field in cachet 2.4
* Updating components via incidents should no longer cause a 400 error if
`component_id` or `component_status` is missing

* Added missing resource imports in `v1.__init__`
* Removed irrelevant `__version__` value in `cachetclient.v1.__init__`

* Added support for schedules (cachet 2.4)

Additions / Improvements

* Support for metrics and metric points
* Documentation improvements

Breaking changes

* Fixed class name typo: `IncidentUpdate` properly renamed to `IncidentUpdate`
* `IncidentUpdate.permlink` renamed to `permalink` (in line with the actual field name)

* Fix Internal Server Error when creating incidents due to
empty `vars`. (Likely a 2.4+ issue)