* src/ui/call-record-row.ui: Add menu, GtkPopover. Surround existing
elements with GtkEventBox to capture longpress/rightclicks
* src/calls-call-record-row.c: Provide functions emiting "call-delete"
signal, add widgets from ui file
* src/calls-record.c: Add "call-delete" signal
* src/calls-history-box.c: Add callback for "call-delete" signal
* src/calls-record-store.c: Add callback for "call-delete" signal
* src/util.c: Add convenience function calls_find_in_store for finding
items in ListModel
* src/util.h: Add declaration of calls_find_in_store
We change the code for dealing with contacts quite significantly,
adding a new class, CallsBestMatch, in order to encapsulate a lot of
the functionality that was in CallsCallRecordRow.
At present avatars are not rounded and there are no auto-generated
avatars for contacts with no avatar. This work is awaiting discussion
of Apps_Issues#164.
