Register-SolidEdgeAddin with multiple projects in one solution

[Martin-Schultz]

When a VS Solution contains more than one project, the first one is always used for Register-SolidEdgeAddin.

I have a solution with more than one project, i would like to specify the project name for Register-SolidEdgeAddin (e.g. Register-SolidEdgeAddin AddinProject) I propose to add a parameter to the register function that can be used for the project name. if no name is provided, the first project should be used to keep backwards compatibility.

The name can simply be passed to Get-Project

this probably related to #6