Upstream species (#6066)

* Step 1 of porting; grabbed most of the files via patches.

* Add species field to the DB

* Appearance patches for slimes.

* Fix the db test.

* Add slime's biocompat.

* slimby

* Fixes, allow specifying if a species is playable or not.

* Update Content.Client/Preferences/UI/HumanoidProfileEditor.xaml.cs

Co-authored-by: Javier Guardia Fernández <DrSmugleaf@users.noreply.github.com>

* Update Content.Client/Preferences/UI/HumanoidProfileEditor.xaml.cs

Co-authored-by: Javier Guardia Fernández <DrSmugleaf@users.noreply.github.com>

* Update Content.Client/Preferences/UI/HumanoidProfileEditor.xaml.cs

Co-authored-by: Javier Guardia Fernández <DrSmugleaf@users.noreply.github.com>

* Address reviews.

* Address reviews.

* make an if-case.

* Fix a goof where species wouldn't get shown in the editor correctly (it'd always default to human)

Co-authored-by: Javier Guardia Fernández <DrSmugleaf@users.noreply.github.com>

Content.Shared/Body/Part/BodyPartCompatibility.cs

@@ -4,6 +4,7 @@ using Robust.Shared.Serialization;
 
 namespace Content.Shared.Body.Part
 {
+    //TODO: This should be a prototype. --DrSmugleaf
     /// <summary>
     ///     Determines whether two <see cref="SharedBodyPartComponent"/>s can connect.
     /// </summary>
@@ -12,6 +13,7 @@ namespace Content.Shared.Body.Part
     {
         Universal = 0,
         Biological,
-        Mechanical
+        Mechanical,
+        Slime
     }
 }