Fix the asset maker

Fixes:

#16
#15

Full Changelog: v2.1.0...v2.1.1

Support OctoberCMS 3.1

v2.1.0

doc: add version

fix: fixes the issue in LINK_POLICY

v2.0.2

fix: add resolver and url service provder to fix Link Policy

ix where the backend skin does not fetch the custom themes

v2.0.1

fix: change the config to use backend.skin

fix!: compatibility fix for v3 and v2

BREAKING CHANGE: The changes will break the octobercms version 1

Minor fix for url generator

Fix #10

Setting UI for Backend Skin

Added setting ui for backend skin

Use extends for url instead of singleton

1.1.2

Update version file

Update Asset Maker and Add Custom Url Generator

Fix issue #7
Fix issue #6

Add separation of backendskin and theme

[FEATURE] Add separation of backendskin and theme

Add new method on defining skin code