Pipenv update doc

[rfoliva]

• Include section on pipenv.
• Clean up .rst files with trailing spaces, long lines and inconsistent section headers.

[codecov-io]

Codecov Report

Merging #438 into master will decrease coverage by 0.5%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #438      +/-   ##
==========================================
- Coverage    74.9%   74.39%   -0.51%     
==========================================
  Files           5        5              
  Lines         785      785              
  Branches      228      228              
==========================================
- Hits          588      584       -4     
- Misses        145      148       +3     
- Partials       52       53       +1

Impacted Files	Coverage Δ
tmuxp/workspacebuilder.py	88.48% <0%> (-2.43%)	⬇️

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[rfoliva]

Updated doc on Pipenv ready for merge @tony .

[tony]

Nice! @rfoliva

Aside: Would you like maintainer privileges for tmuxp/libtmux? I'm looking to expand so more can participate

[rfoliva]

@tony - I would be very happy to help.

Thanks for the extending the invitation!

[tony]

@rfoliva Invited.

[rfoliva]

@tony - Thanks.... I will start taking a look into it this evening. Thanksgiving weekend here in Canada! :)

[tony]

@rfoliva Sounds good. Enjoy your holiday! :)

[rfoliva]

@tony I checked and it seems I need to be given Admin or at least Write permissions in order to be able to handle issues and PRs within the organization.

Here is the link for reference:
https://help.github.com/articles/repository-permission-levels-for-an-organization/

Thanks!