chore: release Erlang R16B03

- Provide a better install experience by cleaning up installed versions
   in the erl 5.10 series and their inclusion in PATH

Erlang16/tools/chocolateyInstall.ps1

@@ -1,11 +1,48 @@
 $package = 'Erlang'
-$version = 'R16B01'
-$installFolder = 'erl5.10.2'
+$version = 'R16B03'
+$installFolder = 'erl5.10.4'
 $releaseFolder = "$installFolder\releases\$version"
 
+function Remove-PreviousVersions
+{
+  $filter = 'erl5.10*'
+  $installs = (Get-ChildItem ${Env:\ProgramFiles(x86)} -Filter $filter) +
+    (Get-ChildItem $Env:ProgramFiles -Filter $filter)
+
+  $installs |
+    Get-ChildItem -Filter 'Uninstall.exe' |
+    Select -ExpandProperty FullName |
+    % {
+      $uninstallParams = @{
+        PackageName = $package;
+        FileType = 'exe';
+        SilentArgs = '/S';
+        File = $_;
+      }
+
+      try
+      {
+        # including additions to PATH
+        $binPath = (Join-Path (Split-Path $_) 'bin') -replace '\\', '\\'
+
+        $userPaths = [Environment]::GetEnvironmentVariable('Path', 'User') -split ';' |
+          ? { ($_ -notmatch $binPath) -and (![String]::IsNullOrEmpty($_)) } |
+          Select-Object -Unique
+
+        [Environment]::SetEnvironmentVariable('Path', ($userPaths -join ';'), 'User')
+
+        Uninstall-ChocolateyPackage @uninstallParams
+      }
+      catch [Exception]
+      {
+        Write-Warning "Could not properly uninstall existing Erlang from $($uninstallParams.File):`n`n$_"
+      }
+    }
+}
+
 try {
 
-  $installedPath = (Join-Path "${Env:\ProgramFiles(x86)}" $installFolder),
+  $installedPath = (Join-Path ${Env:\ProgramFiles(x86)} $installFolder),
     (Join-Path $Env:ProgramFiles "$installFolder\bin") |
     ? { Test-Path $_ } |
     Select -First 1
@@ -17,6 +54,9 @@ try {
   }
   else
   {
+    # first remove previous R16 releases if found
+    Remove-PreviousVersions
+
     $params = @{
       PackageName = $package;
       FileType = 'exe';
@@ -41,4 +81,3 @@ try {
   Write-ChocolateyFailure $package "$($_.Exception.Message)"
   throw
 }
-