Update documentation guide (fixes #3275)
Refer to Sphinx 1.2.3 explicitly in instructions.
Signed-off-by:James L Parry <jim_parry@bcit.ca>
Reverts user guide layout to default.

Refer to Sphinx 1.2.3 explicitly in instructions.  (fixes #3275)
Default layout, tailored, eliminates the dependence on EllisLab layout (fixes #2605)
Navigation is improved by the aboce (fixes #2354)
Signed-off-by:James L Parry <jim_parry@bcit.ca>