NuGet install script throws error

When installing from NuGet, if the `FodyWeaver.xml` does not contain a reference to `PropertyChanged` I get the following error.

    PM> Install-Package PropertyChanged.Fody
    Successfully installed 'PropertyChanged.Fody 1.33.0.0'.
    Successfully added 'PropertyChanged.Fody 1.33.0.0' to ClassLibrary1.
    Cannot convert value "PropertyChanged" to type "System.Int32". Error: "Input string was not in a correct format."
    At D:\src2\ClassLibrary1\packages\PropertyChanged.Fody.1.33.0.0\Tools\install.ps1:14 char:22
    + $node = $xml.Weavers[ <<<< $addinName]
        + CategoryInfo          : NotSpecified: (:) [], RuntimeException
        + FullyQualifiedErrorId : RuntimeException

This fixes that error.

Also added code to find the PropertyChanged reference and set it to CopyLocal false. This stops Costura from embedding the assembly, and other niceties.