+ improve checks in test/configure for X libraries, from xterm #267
changes.
+ modify test/configure to allow it to use the build-tree's libraries
e.g., when using that to configure the test-programs without the
rpath feature (request by Sven Joachim).
+ repurpose "gnome" terminfo entries as "vte", retaining "gnome" items
for compatibility, but generally deprecating those since the VTE
library is what actually defines the behavior of "gnome", etc.,
since 2003 -TD