Added missing dependencies, pre-requisites from
http://sourceforge.net/apps/trac/openxenmanager/wiki/GettingStarted:

py-gtk2, gtk-vnc, shared-mime-info and graphviz.
Updated sysutils/openxenmanager to 0.0.80nb1
Remove squid27.
Remove squid27 package.  It is squid-2.7.STABLE9 which isn't supported
any more.
Note remove of www/squid27 package.
Remove typo3_46.
Remove typo3_46 package, TYPO3 4.6.18 which isn't supported any more.
Note remove of www/typo3_46 package.
RUBY_COMMANDS aren't specific to ruby193 but they will be also needed
by ruby200.
* Properly handle the case of multiple values in RUBY_VERSION_SUPPORTED.
* Clean up PLIST_VARS.

No functional change should be done.