Add: Documentation for local user inventory

Parses /etc/shadow and /etc/passwd and report on discovered users and
attributes. Additional bundles available for augmenting Mission Portal
Inventory UI.

Ref: https://dev.cfengine.com/issues/6213
Merge pull request #858 from nickanderson/redmine/6213

Add: Documentation for local user inventory
Added todo markers to comments in file compare policy
Merge pull request #888 from KevWright/master

Added todo markers to comments in file compare policy