This patch changes the format of Stackviz docs so that all information
is stored in the appropriate doc/source/ directory rather than all
in README.rst. README.rst now just uses the RST include directive to
get its text from doc/source/readme.rst. Usage and installation are
now in their own RST files for increased modularity, and are included
in doc/source/readme.rst.
Additional developer documentation has also been created at
doc/source/man/ and includes more information on stackviz-export
as well as the AngularJS front-end.
Change-Id: I1d37194add998cf83a66d380ec7390e31184bdb3
f3848085e1