removed the qt gui from sflphone

src/gui/official/images/dtmf_6_off.png

src/gui/official/images/dtmf_6_on.png

src/gui/official/images/dtmf_7_off.png

src/gui/official/images/dtmf_7_on.png

src/gui/official/images/dtmf_8_off.png

src/gui/official/images/dtmf_8_on.png

src/gui/official/images/dtmf_9_off.png

src/gui/official/images/dtmf_9_on.png

src/gui/official/images/dtmf_close_off.png

src/gui/official/images/dtmf_close_on.png

src/gui/official/images/dtmf_main.png

src/gui/official/images/dtmf_off.png

src/gui/official/images/dtmf_on.png

src/gui/official/images/dtmf_pound_off.png

src/gui/official/images/dtmf_pound_on.png

src/gui/official/images/dtmf_star_off.png

src/gui/official/images/dtmf_star_on.png

src/gui/official/images/gsm.png

src/gui/official/images/hangup_off.png

src/gui/official/images/hangup_on.png