- API/CLI/Tcl/GUI: new output option BARCODE_BIND_TOP/--bindtop/

`-bindtop`/"Bind Top"
- DPD: add top boundary (width 3X) by default, using new
  BARCODE_BIND_TOP; "relabel" option; some compliance checks
- GUI: only skip encoded/errored signal processing if active modal
  ExportDialog (wasn't clearing/setting error text bar correctly
  for DataDialog)
- CODE128: debug print checksum
- CODE49/DATAMATRIX/QR/ULTRA: fix uniqueness of errtxt nos
- manual: fuller DPD doc; some spelling typos, formatting

frontend_qt/resources.qrc

@@ -16,6 +16,7 @@
         <file>grpDBExtend.ui</file>
         <file>grpDM.ui</file>
         <file>grpDotCode.ui</file>
+        <file>grpDPD.ui</file>
         <file>grpGrid.ui</file>
         <file>grpHX.ui</file>
         <file>grpITF14.ui</file>