Spice tests updates/extensions (v3) (was #1076)

(was #1076)
* Added support for launching remote-viewer with using ".vv" text file containing parameters.
* Added support for spice connection over Spice proxy.
* Rewrote rv input tests from using wxPython to pygtk.
* Minor changes (removing clearx tests and place the code into specific tests, ...).

v2
* Use RHEL-6-spice.ks
* Move deploy_epel_repo() to utils_spice

v3
* Address review comments