(#1994) Switch from minimum installation of .NET 4.0 to .NET 4.5

[TonyT78]

Resolves #1994

Using the guidelines from Microsoft's documentation to determine which .NET Framework version is installed on the machine.

Updated the .NET Framework installer path to point to version 4.5.

Updated the error message to inform the user to install the .NET Framework 4.5.

[CLAassistant]

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[ferventcoder]

This looks good! I'll put this up for vNext!

[gep13]

@TonyT78 thanks again for this PR. In order to move forward with this, are you in a position to sign the CLA?

[gep13]

@TonyT78 thank you for taking the time to create this PR, however, this work will be replaced by the work that is completed as part of #2738 We have decided to jump to .NET 4.8 rather than 4.5.