Take module version into account for -SaveDscDependency switch

[bergmeister]

PR Summary

Fixes #1079 and removes some old dead code.
This is a minimum viable implementation so that we cater for the version as well. It can parse now e.g. Import-DscResource -ModuleName MyModuleName -ModuleVersion 1.2.3.4, before it could not handle the ModuleVersion parameter.
It does not cover cases when not using named parameters or the parameter sets where multiple modules are being used or the (rather old) form of the module specification syntax (e.g. –ModuleName @{ModuleName="xPSDesiredStateConfiguration";ModuleVersion="8.3.0.0"}

PR Checklist

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[JamesWTruher]

lgtm