* lisp/ob-python.el (org-babel-python-mode): adding configuration
option to allow users to control whether they use python.el or
python-mode.el
(org-babel-python-initiate-session-by-key): updated for use with new
configuration option
For some reason ob-R refuses to compile when it requires ob-comint.
When (require 'ob-comint) is not included in ob-R.el everything
compiles without error, but warnings are thrown because the
arguments to a macro defined in ob-comint are mis-interpreted as
functions.
When (require 'ob-comint) is added to ob-R.el then it throws errors
complaining that the last argument to a function is nil and should
be a string. I don't understand this error at all and can't fix it.