PR06 doc string fixes
This PR contains doctrine PR06 fixes mostly doing the conversion below(not that many left to fix :)):

boolean to bool

string to str

integer to int

Tests unchanged

black pandas ran successfully
Thanks @tolaa001 . can you merge master. some of these look familiar. Hello @tolaa001! Thanks for updating this PR. We checked the lines you've touched for [PEP 8](https://www.python.org/dev/peps/pep-0008) issues, and found:



































There are currently no PEP 8 issues detected in this Pull Request. Cheers! :beers: 

##### Comment last updated at 2019-10-13 17:49:47 UTC Thanks @tolaa001 