perl-net-ssleay: fix build

cc_runtime.h is present in old perl distribution
perl: remove documentation in target tree
perl: remove useless modules in target tree

with BR, we never install module from the target
perl-xml-libxml: fix build

see http://autobuild.buildroot.net/results/f80/f809c99ce4db80e64ca46865fcd9b75b0dcc1fcd/
perl-curses: new package
perl-gd: new package
perl-gdtextutil: new package
perl-gdgraph: new package