(universal-usb-installer) Treat trailing character as a additional ve…

…rsion number

This commit updates the automatic updater to treat any trailing character
as its own number to be appended to the last version part, this allows us to
create a new package version even when the software developer has created
a new version without using a pure version number.

ref chocolatey-community#2187

automatic/universal-usb-installer/update.ps1

@@ -16,6 +16,18 @@ function global:au_SearchReplace {
     }
   }
 }
+
+function Convert-CharacterToNumber {
+  param(
+    [Parameter(Mandatory)]
+    [char] $character
+  )
+
+  $newNum = ([int]$character) + 1
+
+  $newNum - [int]([char]'a')
+}
+
 function global:au_GetLatest {
   $download_page = Invoke-WebRequest -Uri $releases -UseBasicParsing
 
@@ -27,6 +39,13 @@ function global:au_GetLatest {
 
   $verRe = '[-]|\.exe$'
   $version32 = $url32 -split "$verRe" | Select-Object -Last 1 -Skip 1
+
+  if ($version32 -match "^([\d\.]+)([a-z])$") {
+    $m1 = $Matches[1]
+    $num = Convert-CharacterToNumber $Matches[2]
+    $version32 = "${m1}$num"
+  }
+
   @{
     URL32   = $url32
     Version = Get-FixVersion $version32 -OnlyFixBelowVersion $padVersionUnder