create script to increment project versions

each time we want to up the version number of the nuget package it involves opening every csproj and manually updating the version. this script updates the version for all projects, except the test project, in the 'src' folder.

tools/set-version.ps1

@@ -0,0 +1,13 @@
+param (
+  [Parameter(Position=0,mandatory=$true)]
+  [string]$version
+)
+
+$projs = Get-ChildItem "../src" -Recurse | Where-Object { $_.extension -eq ".csproj" -and $_.name.IndexOf("Tests") -lt 0 }
+$projs | ForEach-Object {
+  $xml = New-Object XML
+  $xml.Load($_.FullName)
+  $xml.Project.PropertyGroup[0].Version = $version
+  $xml.Save($_.FullName)
+}
+Write-Host $projs.Length