Have an option for about.py to input a filter list to generate data for the filtered components

[chinyeungli]

A project can contains many ABOUT files. However, sometimes, user may not be interested to have all the ABOUT files' information in the output spreadsheet. Instead, they may only be interested in subset of it.
As a result, it'll be convenience for user to input a filter list and ask the tool to only get the information from the filtered ABOUT files.

[mjherzog]

The most common case will be to generate a list based on a Product BOM - i.e. a list of Deployed components.

[DennisClark]

appears to be closed by mistake. re-opening.

[chinyeungli]

similar issue #139

[chinyeungli]

This is different than #139. This issue is about inventory subset of ABOUT files while the #139 is about the format of the inventory