Add compliant height, using ZINT_COMPLIANT_HEIGHT flag for back-compatibility

Rename barcode funcs to same as BARCODE_XXX name
library: barcode funcs array for dispatch, used for ZBarcode_ValidID() also
general: change is_sane() comparison to nonzero from ZINT_ERROR_INVALID_OPTION
MAILMARK: fuller error messages
CODABAR: add option to show check character in HRT
zint.h: use 0xNNNN for OR-able defines
GUI: add guard descent height reset button, add Zint version to window title,
  static get_zint_version() method, use QStringLiteral (QSL shorthand),
  use SIGNAL(toggled()), add errtxt "popup" and status bar, add icons,
  add saveAs shortcut, add main menu, context menus and actions, add help,
  reset_view() -> reset_colours(), add copy to clipboard as EMF/GIF/PNG/TIF,
  lessen triggering of update_preview(), shorten names of getters/setters,
  simplify/shorten some update_preview() logic in switch,
  CODEONE disable structapp for Version S
qzint.cpp: add on_errored signal, add missing getters, add test

frontend_qt/grpGrid.ui

@@ -37,6 +37,9 @@
      </item>
      <item row="0" column="1">
       <widget class="QComboBox" name="cmbGridSize">
+       <property name="maxVisibleItems">
+        <number>14</number>
+       </property>
        <property name="toolTip">
         <string>Set size (version) of symbol</string>
        </property>
@@ -197,7 +200,8 @@ error correction codewords</string>
       <bool>false</bool>
      </property>
      <property name="toolTip">
-      <string>Use Hanzi multibyte encoding for binary and Latin data</string>
+      <string>Use Hanzi multibyte encoding for binary
+and Latin data</string>
      </property>
     </widget>
    </item>