3D viewer: explicitly set synapse marker opacity to 1.0

Before it was 0,6, but this value was never used. Connector edges and
partner nodes where, however, always rendered with an opacity of 1.0. It
turned out to be never actually set on the connector related geometry.
The new (instanced) buffer geometry does however respect the opacity
setting and caused the relevant geometry to be rendered transparent.
Therefore, the actual material definition had to be changed to one to
get the same look as before.

django/applications/catmaid/static/js/widgets/3dviewer.js

@@ -2064,9 +2064,9 @@
     this.labelColors = {uncertain: makeMaterial({color: 0xff8000, opacity:0.6, transparent: true}, this.labelColors, 'uncertain'),
                         todo:      makeMaterial({color: 0xff0000, opacity:0.6, transparent: true}, this.labelColors, 'todo'),
                         custom:    makeMaterial({color: 0xaa70ff, opacity:0.6, transparent: true}, this.labelColors, 'custom')};
-    this.synapticColors = [makeMaterial({color: 0xff0000, opacity:0.6, transparent:false}, this.synapticColors, 0),
-                           makeMaterial({color: 0x00f6ff, opacity:0.6, transparent:false}, this.synapticColors, 1),
-                           makeMaterial({color: 0x9f25c2, opacity:0.6, transparent:false}, this.synapticColors, 2)];
+    this.synapticColors = [makeMaterial({color: 0xff0000, opacity:1.0, transparent:false}, this.synapticColors, 0),
+                           makeMaterial({color: 0x00f6ff, opacity:1.0, transparent:false}, this.synapticColors, 1),
+                           makeMaterial({color: 0x9f25c2, opacity:1.0, transparent:false}, this.synapticColors, 2)];
     this.synapticColors.default = makeMaterial({color: 0xff9100, opacity:0.6, transparent:false}, this.synapticColors, 'default');
   };