* tools/dev/unix-build/Makefile.svn   (sign-email): Figure out perl version in an easier way.
* tools/dev/unix-build/Makefile.svn
  (sign-email): Figure out perl version in an easier way.

Suggested by: danielsh

jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion