adding rate-limit and request options usage to README (xdevplatform#238)

* adding rate-limit and request options usage to README

* bump version

- need to release a new version due to Python 2 retire

bump version (xdevplatform#236)

Minor updates (xdevplatform#227)

* Separate analytics class from resouce.py

* Add some missing endpoints

* bump version

minor bug fix (xdevplatform#225)

- parameter (line_item_ids) needs to be a list

bump version (xdevplatform#220)

bump version (xdevplatform#207)

to 5.2.0

bump version (xdevplatform#195)

Support Python 3.5+ and drop 3.3/3.4 (EOL) (xdevplatform#194)

Update active entities example (xdevplatform#183)

* Update `date_range` to fetch entire day

* format comments (lowercase)

Update Python SDK to v4 (xdevplatform#174)

* v4 Updates

* removed/updated in v4

* minor typo

* fix flake8 errors

* more flake8 fixes

* finally fixed flake8

* fix under-indented lines