fix: Erlang bin path to user PATH, don't reinst

- 100MB download was running again, even if installed already
 - need to ensure the bin dir is in PATH for access to erl
 - Handle PATH manip in install and uninstall

Erlang16/tools/chocolateyInstall.ps1

@@ -1,17 +1,40 @@
 $package = 'Erlang'
 $version = 'R16B01'
+$installFolder = 'erl5.10.2'
+$releaseFolder = "$installFolder\releases\$version"
 
 try {
-  $params = @{
+
-    PackageName = $package;
+  $installedPath = (Join-Path "${Env:\ProgramFiles(x86)}" $installFolder),
-    FileType = 'exe';
+    (Join-Path $Env:ProgramFiles "$installFolder\bin") |
-    #uses NSIS installer - http://nsis.sourceforge.net/Docs/Chapter3.html
+    ? { Test-Path $_ } |
-    SilentArgs = '/S';
+    Select -First 1
-    Url = "http://www.erlang.org/download/otp_win32_$($version).exe";
+
-    Url64Bit = "http://www.erlang.org/download/otp_win64_$($version).exe";
+  # only way to test for installation of this version is by path on disk
+  if (Test-Path $installedPath)
+  {
+    Write-Host "$package $version is already installed to $installedPath"
+  }
+  else
+  {
+    $params = @{
+      PackageName = $package;
+      FileType = 'exe';
+      #uses NSIS installer - http://nsis.sourceforge.net/Docs/Chapter3.html
+      SilentArgs = '/S';
+      Url = "http://www.erlang.org/download/otp_win32_$($version).exe";
+      Url64Bit = "http://www.erlang.org/download/otp_win64_$($version).exe";
+    }
+
+    Install-ChocolateyPackage @params
   }
 
-  Install-ChocolateyPackage @params
+  $binPath = (Join-Path "${Env:\ProgramFiles(x86)}" $installFolder),
+    (Join-Path $Env:ProgramFiles "$installFolder\bin") |
+    ? { Test-Path $_ } |
+    Select -First 1
+
+  Install-ChocolateyPath $binPath
 
   Write-ChocolateySuccess $package
 } catch {

Erlang16/tools/chocolateyUninstall.ps1

@@ -19,6 +19,14 @@ try
   }
 
   Uninstall-ChocolateyPackage @uninstallParams
+
+  $binLocation = Join-Path $installPath 'bin'
+  $userPaths = [Environment]::GetEnvironmentVariable('Path', 'User') -split ';' |
+    ? { ($_ -notmatch $binLocation) -and (![String]::IsNullOrEmpty($_)) } |
+    Select-Object -Unique
+
+  [Environment]::SetEnvironmentVariable('Path', ($userPaths -join ';'), 'User')
+
   Write-ChocolateySuccess $package
 }
 catch