Fix #896 -- support hooks in templates.

Signed-off-by: Chris “Kwpolska” Warrick <kwpolska@gmail.com>
document and add hacks to template_hooks

Signed-off-by: Chris “Kwpolska” Warrick <kwpolska@gmail.com>
add code example for wants_site_and_context=True

Signed-off-by: Chris “Kwpolska” Warrick <kwpolska@gmail.com>
fix python 3

Signed-off-by: Chris “Kwpolska” Warrick <kwpolska@gmail.com>
flake8

Signed-off-by: Chris “Kwpolska” Warrick <kwpolska@gmail.com>
Will diff -bw come out to play?

Signed-off-by: Chris “Kwpolska” Warrick <kwpolska@gmail.com>
Merge branch 'master' into template-hooks

Conflicts:
	CHANGES.txt