Refactoring tone and anouncement gerneration

Move all tones and anouncements into libtones. Each application can name
the tone set (american, german, uk, ect.) during initializaton. The
tones are converted to samples of the target codec. These samples can
then be streamed by the application.

The application of osmocom-analog is the call control of libmobile.

configure.ac

@@ -93,6 +93,7 @@ AC_CONFIG_FILES([src/liblogging/Makefile
     src/libv27/Makefile
     src/libmtp/Makefile
     src/libaaimage/Makefile
+    src/libtones/Makefile
     src/anetz/Makefile
     src/bnetz/Makefile
     src/cnetz/Makefile