Organize cmdlet spec via module name

[dingmeng-xue]

Description

Current cmdlet online specs are organized by RegularExpression. This PR introduces a new approach of organizing cmdlets by their module name.

1. CreateMappings_rules.json contains a new attribute module
2. Calculate module name per each cmdlet and use configured alias if module name is found in configuration file. The rule of module name is prior to RegularExpression
3. Fix duplicated cmdlet claimed in Az.CosmosDB.psd1

Checklist

• I have read the Submitting Changes section of CONTRIBUTING.md
• The title of the PR is clear and informative
• The appropriate ChangeLog.md file(s) has been updated:
  • For any service, the ChangeLog.md file can be found at src/{{SERVICE}}/{{SERVICE}}/ChangeLog.md
  • A snippet outlining the change(s) made in the PR should be written under the ## Upcoming Release header -- no new version header should be added
• The PR does not introduce breaking changes
• If applicable, the changes made in the PR have proper test coverage
• For public API changes to cmdlets:
  • a cmdlet design review was approved for the changes in this repository (Microsoft internal only)
    • {Please put the link here}
  • the markdown help files have been regenerated using the commands listed here