Rebase fix grad

Fixes for tests with --batch option

This is to avoid confusion / conflict with the --verbose option of
nosetests.

* Tests of `trunc` and `trunc_inplace` Ops were testing `floor` instead
  of `trunc`.

* Inplace test for `conj` was using the non inplace version of `conj`.

This option can be used to help debug the --batch option, when
re-running failed tests does not work properly.

This commit also gets rid of some duplicated documentation to prevent it
from getting outdated (it already was a bit outdated since it was not
listing all options available).

This solves some crashes when running ``theano-nose`` with option
``--batch``.

Fix some tests. We where always using the wrong mode.

There is still a problem that make 3 tests fail, but PL will look at it next week.

Small

Make the Rop_Checker init the rng by default.