[U] Only import PSColor if exists

powershell.ps1

@@ -66,6 +66,7 @@ function cropv($file, $len)
 }
 
 # ls coloring
+if (Get-Module -ListAvailable -Name PSColor) {
     Import-Module PSColor
     $global:PSColor = @{
         File = @{
@@ -95,3 +96,4 @@ $global:PSColor = @{
             Line       = @{ Color = 'White' }
         }
     }
+}