This commit tags code blocks with the appropriate language so that
Sphinx can add syntax highlighting and make them look nicer.
Change-Id: Id8f178110236b1d97015162b148f3e9127251a3a
* Add a tutorial step about the new existing users feature (step 3)
* Move the corresponding feature request to 'implemented' and modify it a bit
* Rename step 2 to "Rally input task format"
* Add tables of contents to the lessons
* Other fixes that make docs more precise
Change-Id: Ic800fdfa3df883f267ddcae2165f804c11699bd0