freetdm: add __USE_BSD to ftdm_os, needed by unistd.h for usleep() and string.h to define strcasecmp()
	 add -Werror even when the compiler is unknown. This is just a work-around to gcc not being detected
	 as GNU by our current standalone build (not bootstrapped through FreeSWITCH)

Signed-off-by: Stefan Knoblich <s.knoblich@axsentis.de>

lang: Update langs - Add pt_PT, update es to have es_ES and es_MX, update mod_say_es and add mod_say_pt (FS-2937)

freetdm: core - moved validation of sigstatus from implementation to core, on sigstatus getters/setters
         core - locking the channel on ftdm_channel_get_sig_status() and ftdm_channel_set_sig_status(),
                but not on ftdm_span_get_sig_status() nor ftdm_span_set_sig_status()
         ftmod_r2 - locking channels on ftdm_r2_get_span_sig_status() and ftdm_r2_set_span_sig_status()

freetdm: ftmod_r2 - updated ftdm_r2_set_channel_sig_status() to notify the user of signaling changes
                    just when specified on docs/sigstatus.txt.
					also updated ftdm_r2_set_span_sig_status(), so that it uses the former to set channels
                    status, instead of doing it directly.

	 ioctl interface in FreeBSD expects unsigned long

freetdm: ftmod_r2 - notify the core when we change the signaling status of a channel or span through the api

         mod_freetdm - created sigstatus api command