* Fixes passlib example in FAQ to reduce the number of rounds to 5000
As stated in issue #15326, the default number for glibc is 5000, where
the default for passlib is 656000.
I actually found out when I spend few hours trying to understand why
ansible was taking almost x3 the time to run a playbook when using a
user with sudo and password (comparared to sudo with NOPASSWD set).
Well, it was because the user was created using ansible and the passlib
example found in the docs' FAQ.
Reducing the numbers of rounds to 5000 will ensure a better experience
with ansible for newcomers when using sudo with a password.
* Fixes passlib example in FAQ to reflect the API changes in passlib 1.7
Method encrypt() was deprecated in 1.7 and renamed to hash(), which
happened almost a year ago.
https://passlib.readthedocs.io/en/stable/lib/passlib.ifc.html#passlib.ifc.PasswordHash.encrypt
* developing_modules.rst is now in dev_guide, sync changes and delete the old version
* Cleaner RST & formatted code
* Tidyup roadmaps
* Link to repomerge
* Pull in abadger's fixes From https://github.com/ansible/ansible/compare/docs-code-block-fixes?expand=1
* Clean docsite/rst (apart from ROADMAP
