Add ability to pass `das_client.py` options via `runTheMatrix.py`.

Similar to `--commands`, it is now possible to specify extra
das_client.py options via `--das-options`.

Usage of this includes, but is not limited to:

- Supporting cached queries, see also dmwm/DAS#4142.
- Running against a test bed instance.
Refactor InputInfo to easily get the list of DAS queries.

This slightly refactors the API of InputInfo to allow easier access to
the actual DAS query(s) given a workflow.
Add option to dump job reports.
Merge pull request #4095 from ktf/extra-runthematrix-options

Extra runthematrix options.
Merge remote branch 'origin/CMSSW_7_0_X' into CMSSW_7_0_X
Merge remote branch 'origin/CMSSW_7_1_X' into CMSSW_7_0_X