* Improve documentation with command lines and defaults.
The advanced documentation coverage skipped the simple approach and didn't
explain fully what to do with the sample commands.
Fixes#1413.
* Fix docs indentation in the MySQL connection string options.
* Desultory docs and docs config fixes.
The website is moving to pgloader.org and readthedocs.io is going to be
integrated. Let's see what happens. The docs build fine locally with the
sphinx tools and the docs/Makefile.
Having separate files for the documentation should help ease the maintenance
and add new topics, such as support for Common Lisp Hackers level docs,
which are currently missing.
