vpxenc: add quantizer histogram display
vpxenc: add quantizer histogram display

Add the --q-hist=n option, which displays a histogram with n buckets for
the quantizer selected on each frame.

Change-Id: I59b020c26b0acae0b938685081d9932bd98df5c9

jdm/libvpx,jacklicn/webm.libvpx,Acidburn0zzz/webm.libvpx,jacklicn/webm.libvpx,thdav/aom,goodleixiao/vpx,sanyaade-teachings/libvpx,abwiz0086/webm.libvpx,mwgoldsmith/libvpx,goodleixiao/vpx,webmproject/libvpx,liqianggao/libvpx,pcwalton/libvpx,genesi/libvpx0,hsueceumd/test_hui,shareefalis/libvpx,cinema6/libvpx,charup/https---github.com-webmproject-libvpx-,jdm/libvpx,turbulenz/libvpx,sanyaade-teachings/libvpx,mwgoldsmith/libvpx,jdm/libvpx,kleopatra999/webm.libvpx,awatry/libvpx.opencl,Laknot/libvpx,mwgoldsmith/vpx,charup/https---github.com-webmproject-libvpx-,hsueceumd/test_hui,mbebenita/aom,liqianggao/libvpx,reimaginemedia/webm.libvpx,Maria1099/webm.libvpx,jmvalin/aom,gshORTON/webm.libvpx,shareefalis/libvpx,Topopiccione/libvpx,lyx2014/libvpx_c,kalli123/webm.libvpx,liqianggao/libvpx,kleopatra999/webm.libvpx,liqianggao/libvpx,smarter/aom,vasilvv/esvp8,running770/libvpx,jdm/libvpx,Acidburn0zzz/webm.libvpx,pcwalton/libvpx,mbebenita/aom,shareefalis/libvpx,n4t/libvpx,goodleixiao/vpx,altogother/webm.libvpx,webmproject/libvpx,zofuthan/libvpx,gshORTON/webm.libvpx,shyamalschandra/libvpx,Laknot/libvpx,cinema6/libvpx,shyamalschandra/libvpx,webmproject/libvpx,kleopatra999/webm.libvpx,reimaginemedia/webm.libvpx,ittiamvpx/libvpx,lyx2014/libvpx_c,Topopiccione/libvpx,rikaunite/gst-opera_libvpx,Suvarna1488/webm.libvpx,abwiz0086/webm.libvpx,mbebenita/aom,shacklettbp/aom,VTCSecureLLC/libvpx,matanbs/webm.libvpx,jacklicn/webm.libvpx,stewnorriss/libvpx,Distrotech/libvpx,gshORTON/webm.libvpx,enmasse-entertainment/libvpx,ittiamvpx/libvpx-1,openpeer/libvpx_new,matanbs/vp982,lyx2014/libvpx_c,felipebetancur/libvpx,genesi/libvpx0,iniwf/webm.libvpx,kalli123/webm.libvpx,sanyaade-teachings/libvpx,vasilvv/esvp8,kim42083/webm.libvpx,pcwalton/libvpx,openpeer/libvpx_new,iniwf/webm.libvpx,turbulenz/libvpx,altogother/webm.libvpx,Topopiccione/libvpx,gshORTON/webm.libvpx,enmasse-entertainment/libvpx,rikaunite/gst-opera_libvpx,luctrudeau/aom,Laknot/libvpx,WebRTC-Labs/libvpx,Maria1099/webm.libvpx,jmvalin/aom,shacklettbp/aom,mbebenita/aom,jdm/libvpx,jmvalin/aom,running770/libvpx,abwiz0086/webm.libvpx,Acidburn0zzz/webm.libvpx,zofuthan/libvpx,openpeer/libvpx_new,n4t/libvpx,felipebetancur/libvpx,turbulenz/libvpx,smarter/aom,smarter/aom,hsueceumd/test_hui,matanbs/webm.libvpx,ittiamvpx/libvpx,matanbs/vp982,Laknot/libvpx,altogother/webm.libvpx,luctrudeau/aom,Maria1099/webm.libvpx,rikaunite/gst-opera_libvpx,matanbs/webm.libvpx,charup/https---github.com-webmproject-libvpx-,webmproject/libvpx,jdm/libvpx,genesi/libvpx0,ittiamvpx/libvpx-1,turbulenz/libvpx,enmasse-entertainment/libvpx,kalli123/webm.libvpx,Distrotech/libvpx,vasilvv/esvp8,charup/https---github.com-webmproject-libvpx-,VTCSecureLLC/libvpx,GrokImageCompression/aom,stewnorriss/libvpx,mwgoldsmith/vpx,pcwalton/libvpx,lyx2014/libvpx_c,hsueceumd/test_hui,enmasse-entertainment/libvpx,mwgoldsmith/libvpx,running770/libvpx,ShiftMediaProject/libvpx,felipebetancur/libvpx,Maria1099/webm.libvpx,kim42083/webm.libvpx,ittiamvpx/libvpx,Suvarna1488/webm.libvpx,Acidburn0zzz/webm.libvpx,reimaginemedia/webm.libvpx,liqianggao/libvpx,abwiz0086/webm.libvpx,hsueceumd/test_hui,running770/libvpx,altogother/webm.libvpx,openpeer/libvpx_new,felipebetancur/libvpx,luctrudeau/aom,stewnorriss/libvpx,webmproject/libvpx,reimaginemedia/webm.libvpx,kleopatra999/webm.libvpx,kim42083/webm.libvpx,matanbs/webm.libvpx,GrokImageCompression/aom,lyx2014/libvpx_c,mbebenita/aom,altogother/webm.libvpx,hsueceumd/test_hui,openpeer/libvpx_new,goodleixiao/vpx,shyamalschandra/libvpx,pcwalton/libvpx,iniwf/webm.libvpx,cinema6/libvpx,running770/libvpx,kim42083/webm.libvpx,Suvarna1488/webm.libvpx,ShiftMediaProject/libvpx,mwgoldsmith/vpx,ittiamvpx/libvpx,felipebetancur/libvpx,Distrotech/libvpx,abwiz0086/webm.libvpx,kleopatra999/webm.libvpx,Acidburn0zzz/webm.libvpx,reimaginemedia/webm.libvpx,matanbs/vp982,WebRTC-Labs/libvpx,openpeer/libvpx_new,matanbs/webm.libvpx,awatry/libvpx.opencl,iniwf/webm.libvpx,shareefalis/libvpx,running770/libvpx,shareefalis/libvpx,vasilvv/esvp8,cinema6/libvpx,sanyaade-teachings/libvpx,Suvarna1488/webm.libvpx,thdav/aom,GrokImageCompression/aom,shyamalschandra/libvpx,stewnorriss/libvpx,genesi/libvpx0,pcwalton/libvpx,ShiftMediaProject/libvpx,jacklicn/webm.libvpx,Suvarna1488/webm.libvpx,Acidburn0zzz/webm.libvpx,kim42083/webm.libvpx,thdav/aom,mwgoldsmith/vpx,mbebenita/aom,ShiftMediaProject/libvpx,ittiamvpx/libvpx-1,stewnorriss/libvpx,shacklettbp/aom,mbebenita/aom,rikaunite/gst-opera_libvpx,awatry/libvpx.opencl,luctrudeau/aom,Suvarna1488/webm.libvpx,kim42083/webm.libvpx,cinema6/libvpx,VTCSecureLLC/libvpx,matanbs/vp982,WebRTC-Labs/libvpx,Topopiccione/libvpx,ittiamvpx/libvpx,luctrudeau/aom,kleopatra999/webm.libvpx,awatry/libvpx.opencl,n4t/libvpx,kalli123/webm.libvpx,matanbs/webm.libvpx,gshORTON/webm.libvpx,charup/https---github.com-webmproject-libvpx-,smarter/aom,zofuthan/libvpx,matanbs/vp982,gshORTON/webm.libvpx,VTCSecureLLC/libvpx,mbebenita/aom,iniwf/webm.libvpx,goodleixiao/vpx,charup/https---github.com-webmproject-libvpx-,shacklettbp/aom,mwgoldsmith/vpx,turbulenz/libvpx,Laknot/libvpx,Topopiccione/libvpx,matanbs/vp982,shacklettbp/aom,jmvalin/aom,felipebetancur/libvpx,smarter/aom,vasilvv/esvp8,thdav/aom,WebRTC-Labs/libvpx,GrokImageCompression/aom,VTCSecureLLC/libvpx,enmasse-entertainment/libvpx,abwiz0086/webm.libvpx,smarter/aom,goodleixiao/vpx,vasilvv/esvp8,n4t/libvpx,mwgoldsmith/libvpx,thdav/aom,lyx2014/libvpx_c,ittiamvpx/libvpx-1,mwgoldsmith/libvpx,cinema6/libvpx,matanbs/vp982,Distrotech/libvpx,Topopiccione/libvpx,ShiftMediaProject/libvpx,jmvalin/aom,GrokImageCompression/aom,kalli123/webm.libvpx,shacklettbp/aom,shyamalschandra/libvpx,jmvalin/aom,turbulenz/libvpx,mwgoldsmith/libvpx,shyamalschandra/libvpx,webmproject/libvpx,iniwf/webm.libvpx,stewnorriss/libvpx,mwgoldsmith/vpx,VTCSecureLLC/libvpx,ittiamvpx/libvpx-1,liqianggao/libvpx,rikaunite/gst-opera_libvpx,sanyaade-teachings/libvpx,ittiamvpx/libvpx-1,turbulenz/libvpx,thdav/aom,zofuthan/libvpx,mbebenita/aom,zofuthan/libvpx,Laknot/libvpx,turbulenz/libvpx,cinema6/libvpx,WebRTC-Labs/libvpx,GrokImageCompression/aom,reimaginemedia/webm.libvpx,jacklicn/webm.libvpx,zofuthan/libvpx,turbulenz/libvpx,Maria1099/webm.libvpx,genesi/libvpx0,vasilvv/esvp8,ittiamvpx/libvpx,Maria1099/webm.libvpx,Distrotech/libvpx,shareefalis/libvpx,n4t/libvpx,altogother/webm.libvpx,Distrotech/libvpx,genesi/libvpx0,kalli123/webm.libvpx,jacklicn/webm.libvpx,luctrudeau/aom