Format doc (from devtools to energy_functions)

Devtools, distributions and energy_functions
Format documention in expr/basic

Includes important changes to the docstring of symGivens2
Format documentation in expr
Format doc in gui (and format)

The change in format is very minor.
Format documentation in linear
Display multiple levels of indentation correctly
Remove tabs
Fix math in expr/basic.py
Add "WRITEME" for some parameters
Merge pull request #768 from sebastien-j/issue-372-2

#372: Fixes docstrings for files under

devtools/
distributions/
energy_functions/
expr/
format/
gui/
linear/