Update master branch version string

Master branch, a.k.a. "trunk" branch for main development, will now have
its numeric version string appended by '~git'.  Per Kamal Mostafa,
KA6MAL, the use of the '~' character causes packaging systems to treat
the version string as an ealier release.  e.g. The Debian packaging
system treats 1.2.14~git as earlier than 1.2.14 which is useful to
avoid confusion after release.

configure.ac

@@ -8,7 +8,7 @@ AC_PREREQ(2.59)
 ## Autoconf initialisation. ##
 ## ------------------------ ##
 dnl Please do not use '-' in the version number, 'make rpm' will fail
-AC_INIT([hamlib],[1.2.14svn],[hamlib-developer@lists.sourceforge.net])
+AC_INIT([hamlib],[1.2.14~git],[hamlib-developer@lists.sourceforge.net])
 AC_CONFIG_SRCDIR([include/hamlib/rig.h])
 AC_CONFIG_MACRO_DIR([macros])