Work towards libfreeswitch compiling on OpenBSD

- Moved contents of libteletone into libfreeswitch
- Moved contents of libtpl into libfreeswitch
- Moved contents of stfu into libfreeswitch
- Remove legacy lib directories for libteletone, libtpl and stfu
- Create OpenBSD centric Makefiles for build infrastructure

Note that we almost can build libfreeswitch now, just need to port the library
to the latest version of miniupnpc, libnatpmp amd libsrtp which have changed in
years since they were pulled into the upstream FS tree.