Annotate J5 and J20 according to their serial protocols in silkscreens.

hardware/dscomm.kicad_pcb

@@ -2,7 +2,7 @@
 
   (general
     (thickness 1.6)
-    (drawings 179)
+    (drawings 181)
     (tracks 1205)
     (zones 0)
     (modules 143)
@@ -3681,7 +3681,7 @@
     (descr "Through hole angled pin header, 1x06, 2.54mm pitch, 6mm pin length, single row")
     (tags "Through hole angled pin header THT 1x06 2.54mm single row")
     (path /60040981/6006812D)
-    (fp_text reference J5 (at -1.75 6.25) (layer F.SilkS)
+    (fp_text reference J5 (at -2 9 90) (layer F.SilkS)
       (effects (font (size 1 1) (thickness 0.15)))
     )
     (fp_text value Conn_01x06_Male (at 4.385 14.97) (layer F.Fab)
@@ -6676,6 +6676,12 @@
     )
   )
 
+  (gr_text SWD (at 232.75 149.5) (layer F.SilkS) (tstamp 5FEAEDD9)
+    (effects (font (size 1 1) (thickness 0.15)))
+  )
+  (gr_text "(UART)" (at 233 140.25 90) (layer F.SilkS) (tstamp 5FEAD418)
+    (effects (font (size 1 1) (thickness 0.15)))
+  )
   (gr_text JTAG (at 227.615 146.25 90) (layer F.SilkS)
     (effects (font (size 1 1.25) (thickness 0.2)))
   )