replaced hardcoded text by enums in some functions

functions/public/Get-Tag.ps1

@@ -1,6 +1,6 @@
 function Get-Tag {
     [CmdletBinding(DefaultParameterSetName="NoParams")]
-    [OutputType('tag')]
+    [OutputType({[types]::tag})]
     param (
         [parameter(Mandatory=$false,ValueFromPipeline=$true,ValueFromPipelineByPropertyName=$true,Position=0,ParameterSetName="ByID")]
         [ValidateScript({ $_ -match "^\d+$" })]
@@ -9,14 +9,18 @@ function Get-Tag {
         $Id,
         [parameter(Mandatory=$false,ValueFromPipeline=$true,ValueFromPipelineByPropertyName=$true,Position=0,ParameterSetName="ByAddressObject")]
         [ValidateNotNullOrEmpty()]
-        [ps.ipam.address]
-        $InputObject
+        [PS.IPAM.Address]
+        $AddressObject,
+        [parameter(Mandatory=$false,ValueFromPipeline=$true,ValueFromPipelineByPropertyName=$true,Position=0,ParameterSetName="BySubnetObject")]
+        [ValidateNotNullOrEmpty()]
+        [PS.IPAM.Subnetwork]
+        $SubnetObject
     )
     process {
         $_params = @{
-            Controller = "addresses"
-            Method     = "GET"
-            Type       = "tag"
+            Controller = [controllers]::addresses
+            Method     = [methods]::GET
+            Type       = [types]::tag
         }
         $_identifiers = @("tags")
         switch ($PSCmdlet.ParameterSetName) {