Adding a simple MongoDB base client

It's not finished, but it's atleast in a workable state.
Edits:
* Replacing Exception per review comments
* Adding pymongo in pip-requires

Change-Id: I620bb501357023a2b2f312f6339c83bb44269191
Fixed bug in remove_empty_values() method

Change-Id: Id6d402c76bd6d9647c23a7e3ce9d32fc6ded4614
Subject: Move logging. Pep8 fixes
Moved logging from runner to cclogging. Pep8 fixes.
re-added tag support. took out colorization

Change-Id: I0c66c232aaf5d21efcf57fa351739655ecee3340
Merge "Adding a simple MongoDB base client"
First pass at JSON file output from runner

* Modified parsers class to return basic results optionally
* Added logic to runner to output JSON file to current directory
* Temporarily disabled xml output (was broken, needs refactoring)

Change-Id: I9b635069a18212a8c83032b52d91c6fb668deb91
Fixing sudo user issue with virtualenvs

Change-Id: I1b590f6f1119b54ac816f8b5f93a9bf465dc07db
Merge "First pass at JSON file output from runner"
Rough pass at correcting the pep8 issues.

Rebasing yet again...
Change-Id: Iaee489e48d135c530984737efd1ade34bf0de49a
Moved dependencies on cloudcafe internally

* Moved partition and file details models into opencafe
* Moved instance constants into opencafe

Change-Id: I4780cfc32e4864b5850aaf0eff8abbc6181c6713
Added command to remote client to retrieve xen metadata

* Adds command to list and parse xen user metadata

Change-Id: I27e8e5dea14c53af23222572d14a72807db56f98
Adding required modules to use opencafe

Change-Id: Iae819ed76b0b25282309acfe03e3168da577309a
Adds key authentication to ssh client

* Adds key param to instance clients
* Added string to private key converter in ssh client

Change-Id: I7ddec4abfcd3338b7d27827204b99492169d4a78
Uncommented necessary dependencies in pip-requires

Change-Id: I9600165b718f5c83f64daf52c1f620a4fda7e40f
Merge "Uncommented necessary dependencies in pip-requires"