Fix Unapproved Verbs and Nested Module Loading Consistency

[X-Guardian]

Change the following exported functions to use approved verbs

Old Function Name	New Function Name
Create-RegistrySettingsEntry	New-RegistrySettingsEntry
Create-GPRegistryPolicyFile	New-GPRegistryPolicyFile
Parse-PolFile	Import-PolFile
Append-RegistryPolicies	Add-RegistryPolicies

Aliases have been added for the old names, so current usage should be unaffected.

Change the Module import to Consistently use NestedModules

Currently each of the nested modules is loaded using a different method. Changed this to both be specified as NestedModules in the main module psd file, and removed the unnecessary Export-ModuleMember commands from each module, as the functions to export are listed in the main module psd file.

[X-Guardian]

Can someone review this PR?