Document environment variables of linux images (#2498)

* Document environment variables of linux images

* Change adnroid variables

* Apply reviews

* Remove some variables, fix headers

* Show link targets

* rename helper

* remove symlinks

* More links

* Dynamic GO variables

* Architecture for  GO variables

* remove GOROOT

images/linux/scripts/SoftwareReport/SoftwareReport.CachedTools.psm1

@@ -28,6 +28,19 @@ function Get-ToolcacheGoVersions {
     return Get-ChildItem $toolcachePath -Name | Sort-Object { [Version]$_ }
 }
 
+function Build-GoEnvironmentTable {
+    return Get-CachedToolInstances -Name "go" -VersionCommand "version" | ForEach-Object {
+        $Version = [System.Version]($_.Version -Split(" "))[0]
+        $Name = "GOROOT_$($Version.major)_$($Version.minor)_X64"
+        $Value = (Get-Item env:\$Name).Value
+        [PSCustomObject] @{
+            "Name" = $Name
+            "Value" = (Get-Item env:\$Name).Value
+            "Architecture" = $_. Architecture
+        }
+    }
+}
+
 function Get-ToolcacheBoostVersions {
     $Name = "Boost"
     $toolcachePath = Join-Path $env:AGENT_TOOLSDIRECTORY "boost"
@@ -82,4 +95,4 @@ function Build-CachedToolsSection {
     $output += New-MDList -Lines (Get-ToolcacheRubyVersions) -Style Unordered
 
     return $output
-}
+}