Backport PR #5832: Fixed example to work with python3

Just some print parentheses added.
Backport PR #5837: pass on install docs

there were many False statements, and no-longer appropriate recommendations to use easy_install.
Backport PR #5839: Close graphics dev in finally clause

closes #4408 (already closed)
Backport PR #5842: fix typo in nbconvert help

Latex template is 'base', not 'basic'
cf. https://github.com/ipython/ipython/tree/master/IPython/nbconvert/templates/latex
Backport PR #5846: Fix typos in Cython example

Just couple of small things.