Add support for pre-release modules in Install-PodeLocalModule

[DanGough]

Describe the Change

I am unable to add pre-release modules to package.json using a setup like below:

    "Pode.Web": {
      "version": "1.0.0-preview2",
      "prerelease": true,
      "repository": "PSGallery"
    },

This would then add the -AllowPreRelease parameter to the Find-Module and Save-Module calls in Install-PodeLocalModule.