doc: Remove stale .images/Branches.png file
doc: Remove stale .images/Branches.png file

Ditaa images are not kept in tree anymore...

wingo/snabbswitch,Igalia/snabb,eugeneia/snabbswitch,wingo/snabb,wingo/snabbswitch,heryii/snabb,heryii/snabb,Igalia/snabbswitch,dpino/snabb,eugeneia/snabbswitch,snabbco/snabb,dpino/snabbswitch,eugeneia/snabb,heryii/snabb,snabbco/snabb,alexandergall/snabbswitch,Igalia/snabbswitch,mixflowtech/logsensor,dpino/snabb,dpino/snabb,snabbco/snabb,kbara/snabb,snabbco/snabb,eugeneia/snabb,wingo/snabb,alexandergall/snabbswitch,heryii/snabb,Igalia/snabbswitch,kbara/snabb,dpino/snabbswitch,dpino/snabb,alexandergall/snabbswitch,dpino/snabb,wingo/snabb,Igalia/snabb,alexandergall/snabbswitch,Igalia/snabbswitch,mixflowtech/logsensor,heryii/snabb,Igalia/snabb,snabbco/snabb,wingo/snabb,eugeneia/snabb,eugeneia/snabbswitch,SnabbCo/snabbswitch,Igalia/snabb,wingo/snabbswitch,kbara/snabb,wingo/snabb,Igalia/snabb,kbara/snabb,Igalia/snabb,snabbco/snabb,eugeneia/snabb,wingo/snabbswitch,alexandergall/snabbswitch,wingo/snabb,kbara/snabb,alexandergall/snabbswitch,eugeneia/snabb,SnabbCo/snabbswitch,Igalia/snabbswitch,mixflowtech/logsensor,SnabbCo/snabbswitch,mixflowtech/logsensor,Igalia/snabb,snabbco/snabb,eugeneia/snabb,Igalia/snabb,mixflowtech/logsensor,eugeneia/snabbswitch,heryii/snabb,kbara/snabb,dpino/snabbswitch,dpino/snabb,alexandergall/snabbswitch,eugeneia/snabb,alexandergall/snabbswitch,eugeneia/snabb,snabbco/snabb,dpino/snabbswitch,dpino/snabb,SnabbCo/snabbswitch