The latest version of livereload does not use the -b option
Move the printing part of the tutorial after the gotchas and basic operations

Pretty printing is not used in the tutorial until after these sections, and
they are more important than printing.
Include simplification
Don't use bullets for the "whet your appetite" section

It just looks bad.
Wording
Note that the printing options are in the settings (which are hidden by default)
Some wording on the "Why SymPy?" section
Spell functions as function() in the printing tutorial
Don't use `` in section titles in the simplification part of the tutorial
Write functions as function() in the simplification section of the tutorial

I have used the convention that Python functions are written as function(),
but SymPy objects (like sin) are not.
Grammar
Grammar
Grammar fix
Grammar
Make the word "tutorial" on the front page a link
Plane class
Removed trailing spaces
Merge https://github.com/sympy/sympy into plane
Changed the are_perpendicular and is_parallel method
Refactor code in projection_line method