F133871: support entity mapping

[graju256]

This PR brings necessary changes for supporting entity mapping feature over graphman

• export
• • new option (--excludeDependencies) to exclude the dependency entities
• • fixed folder query
• explode
• • bundle properties along with the mappings will be written to a file (bundle-properties.json)
• mappings
• • new operation to generate mappings for the existing bundles
• implode
• • manage mappings while imploding the config into bundle
• import
• • manage mappings while importing to the target gateway
• introducing jest based functional tests
• • run the below commands to execute the tests
• • • npm install --save-dev jest
• • • npm test
• POSTMAN collection
• • adding sample queries/mutations for new entities
• • introduced new way of installing/deleting bundled of entities
• updated README as well.

[graju256]

@flascelles @burbanski please approve this PR.

README is updated with the new additions

• about the new operation i.e., mappings
• how to override the mapping actions while importing the bundle
• about standard bundle mutation queries (install-bundle and delete-bundle)

[graju256]

@flascelles @burbanski

POSTMAN collection is also modified. client will be made available as new release (i.e., 1.1.00) FYI, Latest version is not compatible with the older gateways.

[graju256]

@flascelles @burbanski please approve this PR