__package_pip: match package names case insensitive

Pip matches them insensitive, so we need to do the same to avoid
problems by saying extras are not installed but already is there in
place.

cdist/conf/type/__package_pip/explorer/extras

@@ -57,7 +57,8 @@ then
 
         # echo the extra if no packages where found for it
         # if there is no pattern, we don't need to search ;-)
-        if [ "$grep_pattern" ] && ! grep -q "$grep_pattern" "$pip_freeze"
+        # pip matches packages case-insensetive, we need to do that, too
+        if [ "$grep_pattern" ] && ! grep -qi "$grep_pattern" "$pip_freeze"
         then
             echo "$extra"
         fi