reliability, style: return value of main()

If run as a script/module/command call main with no argv and exit
with its return value.

Improved style for argument help messages
style: fixed typo in inline comments (Ppp -> App)
bugfix: fixed inheritance for QueryStore

fixes #65
bugfix: fixed #66 - SimpleIndex preprocessing
reliability: LxmlParser copies `id` attr from Document to Record
+func: added ComponentParentTransformer

ObjectType: ComponentParentFetchingTransformer

Given a Cheshire3 component Record, fetches and returns the data
for the parent as a Document