Fix error handling when there are no edge cuts

Author: qu1ck

InteractiveHtmlBom/core/ibom.py

@@ -273,7 +273,7 @@ def main(parser, config, logger):
     pcbdata, components = parser.parse()
     if not pcbdata or not components:
         logger.error('Parsing failed.')
-        exit(1)
+        return
     pcbdata["bom"]["both"] = generate_bom(components, config, extra_fields)
 
     # build BOM

InteractiveHtmlBom/ecad/kicad.py

@@ -375,7 +375,7 @@ def parse(self):
             self.logger.error('Please draw pcb outline on the edges '
                               'layer on sheet or any module before '
                               'generating BOM.')
-            return
+            return None, None
         bbox = {
             "minx": bbox.GetPosition().x * 1e-6,
             "miny": bbox.GetPosition().y * 1e-6,