Add Start-PSPackage -Type switch to build any output

If not specified, "deb" is used as default on Linux. This should be
updated to check the distribution and required package build
dependencies.

Dependency names switched per package type, since specific package names
are different. Should check if this causes an issue on OS X when the
names are empty.

PowerShellGitHubDev.psm1

@@ -82,7 +82,9 @@ function Start-PSPackage
     # Ubuntu and OS X packages are supported.
     param(
         [string]$Version,
-        [int]$Iteration = 1
+        [int]$Iteration = 1,
+        [ValidateSet("deb", "osxpkg", "rpm")]
+        [string]$Type
     )
 
     if ($IsWindows) { throw "Building Windows packages is not yet supported!" }
@@ -99,13 +101,26 @@ function Start-PSPackage
     chmod -R go=u "$PSScriptRoot/bin"
 
     # Decide package output type
-    $Output = if ($IsLinux) { "deb" } elseif ($IsOSX) { "osxpkg" }
+    if (-Not($Type)) {
+        $Type = if ($IsLinux) { "deb" } elseif ($IsOSX) { "osxpkg" }
+        Write-Warning "-Type was not specified, continuing with $Type"
+    }
 
     # Use Git tag if not given a version
     if (-Not($Version)) {
         $Version = (git --git-dir="$PSScriptRoot/.git" describe) -Replace '^v'
     }
 
+    $libunwind = switch ($Type) {
+        "deb" { "libunwind8" }
+        "rpm" { "libunwind" }
+    }
+
+    $libicu = switch ($Type) {
+        "deb" { "libicu52" }
+        "rpm" { "libicu" }
+    }
+
     # Build package
     fpm --force --verbose `
         --name "powershell" `
@@ -117,12 +132,12 @@ function Start-PSPackage
         --license "Unlicensed" `
         --description "Open PowerShell on .NET Core\nPowerShell is an open-source, cross-platform, scripting language and rich object shell. Built upon .NET Core, it is also a C# REPL.\n" `
         --category "shells" `
-        --depends "libunwind8" `
-        --depends "libicu52" `
+        --depends $libunwind `
+        --depends $libicu `
         --deb-build-depends "dotnet" `
         --deb-build-depends "cmake" `
         --deb-build-depends "g++" `
-        -t $Output `
+        -t $Type `
         -s dir `
         "$PSScriptRoot/bin/=/usr/local/share/powershell/" `
         "$PSScriptRoot/package/powershell=/usr/local/bin"