fix(formatting): Make formats parse specs as-is

This removes the spacing tinkering when parsing format specs.
The following example uses the old behavoir:

    format-test = <label-foo>  <label-bar>
    format-breaks = <label-foo><label-bar>/<bar-test>

`format-test` would replace all occurences of ' ' with the
a space string with defined `spacing` as its width. `format-breaks` would
not validate as the tags where split with ' ' as delimiter.

All that nonsense has been removed and each tag is extracted as is.
The `spacing` parameter can still be used to apply N extra whitespaces
between the tags, but it is now 0 by default.

src/components/builder.cpp

@@ -301,7 +301,11 @@ void builder::offset(int pixels) {
  * Insert spaces
  */
 void builder::space(size_t width) {
-  m_output.append(width, ' ');
+  if (width) {
+    m_output.append(width, ' ');
+  } else {
+    space();
+  }
 }
 void builder::space() {
   m_output.append(m_bar.spacing, ' ');