Missing dependency against python-jsonschema

[Javier Collado]

Once the python-jsonschema package is available in the precise PPA for utah, a dependency should be added against this package to make sure is installed for both utah and utah-client packages since both of them will make use of the jsonschema validation functionality.

In addition to this, the code in package maintainer scripts that takes care of installing the the same library using "pip install" should be removed, since it's no longer needed and, besides this, is failing in lab environment without access to pypi.