Fix some minor coverity warnings. Fix a bug in pcad2kicad plugin. Scripting: map BASE_SET. Rename some python bom scripts with better names. Fix erroneous comments and add comments

scripts/bom-in-python/bom_html_with_advanced_grouping.py

@@ -1,7 +1,7 @@
 #
 # Example python script to generate a BOM from a KiCad generic netlist
 #
-# Example: Sorted and Grouped HTML BOM with more advanced grouping
+# Example: Sorted and Grouped HTML BOM with advanced grouping
 #
 
 """
@@ -75,7 +75,7 @@ def myEqu(self, other):
 kicad_netlist_reader.comp.__equ__ = myEqu
 
 # Generate an instance of a generic netlist, and load the netlist tree from
-# video.tmp. If the file doesn't exist, execution will stop
+# <file>.tmp. If the file doesn't exist, execution will stop
 net = kicad_netlist_reader.netlist(sys.argv[1])
 
 # Open a file to write too, if the file cannot be opened output to stdout

scripts/bom-in-python/kicad_netlist_reader.py

@@ -9,10 +9,8 @@
 
 """
     @package
-    Generate a HTML BOM list.
-    Components are sorted and grouped by value
-    Fields are (if exist)
-    Ref, Quantity, Value, Part, Datasheet, Description, Vendor
+    Helper module for interpreting generic netlist and build custom
+    bom generators or netlists in foreign format
 """