(FACT-375) Remove Fedora 18 from acceptance nodes

Fedora 18 is EOL so we no longer need to test against it.
(FACT-375) Add rhel7 to acceptance configs
(FACT-375) add acceptance configs for fedora{19,20}
(FACT-375) Add acceptance configs for solaris 10
(FACT-375) Reorganize acceptance pre-suite
(FACT-375) Install json from system packages in acceptance tests
(FACT-375) cd into acceptance dir when initializing
(FACT-375) Update apt after installing new repo