Use PORTAUDIO_LIBS variable to compile libportaudio.la with -lflags (-lasound)

Re-enable register button in configuration panel ui
Todo: to send a popup if the registration has failed or connected
Todo: use the account arg on the server

Use -DDEBUG when the user set --enable-debug=full
Use -g only if --enable-debug=yes
Don't use -02 if --enable-debug=full

Refactoring --enable-options code

Disable speex by default
Didn't find the cause yet to const SpeexMove/SpeexMove bug seen on some ubuntu distribution