debug: add pretty printer for events
debug: add pretty printer for events

Adder is using GST_PTR_FORMAT for events already, so we might actualy
implement this and print out some useful info.

surround-io/gstreamer,Distrotech/gstreamer,ahmedammar/platform_external_gst_gstreamer,drothlis/gstreamer,ensonic/gstreamer,lubosz/gstreamer,jpxiong/gstreamer,lovebug356/gstreamer,Lachann/gstreamer,Distrotech/gstreamer,surround-io/gstreamer,cablelabs/gstreamer,lovebug356/gstreamer,centricular/gstreamer,shelsonjava/gstreamer,cfoch/gstreamer,Lachann/gstreamer,jpxiong/gstreamer,jpxiong/gstreamer,justinjoy/gstreamer,krieger-od/gstreamer,ylatuya/gstreamer,justinjoy/gstreamer,jpxiong/gstreamer,magcius/gstreamer,krichter722/gstreamer,krieger-od/gstreamer,mparis/gstreamer,surround-io/gstreamer,shelsonjava/gstreamer,mparis/gstreamer,cablelabs/gstreamer,mrchapp/gstreamer,cfoch/gstreamer,krichter722/gstreamer,ahmedammar/platform_external_gst_gstreamer,shelsonjava/gstreamer,surround-io/gstreamer,mrchapp/gstreamer,lubosz/gstreamer,StreamUtils/gstreamer,cfoch/gstreamer,centricular/gstreamer,lubosz/gstreamer,magcius/gstreamer,justinjoy/gstreamer,collects/gstreamer,drothlis/gstreamer,Distrotech/gstreamer,StreamUtils/gstreamer,jpakkane/gstreamer,drothlis/gstreamer,drothlis/gstreamer,ylatuya/gstreamer,jpakkane/gstreamer,mparis/gstreamer,ylatuya/gstreamer,cablelabs/gstreamer,shelsonjava/gstreamer,drothlis/gstreamer,jpakkane/gstreamer,Lachann/gstreamer,StreamUtils/gstreamer,magcius/gstreamer,mrchapp/gstreamer,ylatuya/gstreamer,krichter722/gstreamer,krieger-od/gstreamer,krichter722/gstreamer,Distrotech/gstreamer,jpakkane/gstreamer,ahmedammar/platform_external_gst_gstreamer,shelsonjava/gstreamer,collects/gstreamer,centricular/gstreamer,ensonic/gstreamer,lubosz/gstreamer,jpakkane/gstreamer,Lachann/gstreamer,justinjoy/gstreamer,ylatuya/gstreamer,mrchapp/gstreamer,ensonic/gstreamer,magcius/gstreamer,Distrotech/gstreamer,krichter722/gstreamer,cfoch/gstreamer,ahmedammar/platform_external_gst_gstreamer,krieger-od/gstreamer,lovebug356/gstreamer,ahmedammar/platform_external_gst_gstreamer,collects/gstreamer,lubosz/gstreamer,jpxiong/gstreamer,ensonic/gstreamer,mrchapp/gstreamer,StreamUtils/gstreamer,collects/gstreamer,cablelabs/gstreamer,mparis/gstreamer,Lachann/gstreamer,lovebug356/gstreamer,mparis/gstreamer,ensonic/gstreamer,lovebug356/gstreamer,collects/gstreamer,surround-io/gstreamer,cablelabs/gstreamer,centricular/gstreamer,cfoch/gstreamer,magcius/gstreamer,krieger-od/gstreamer,justinjoy/gstreamer,StreamUtils/gstreamer,centricular/gstreamer