LTS v1.0.3 UI fixes

Fixed Seneral#189 toolbar not showing up introduced in f82311c (v1.0.3)
Improved GUISkin handling so that the default GUIStyle are always used
	- Fixes some problems with missing styles at Runtime if not explicitly set, as well as issues when switching between dark and light modes
	- New behaviour: Always generate DefaultSkin and save to file for user to copy and modify. If OverriddenSkin.asset exists, use that style as a basis instead.
Fixed issue with XML IO for objects that can not be serialized (e.g. Texture2D in TextureCompose example)

LTS v1.0.3. GUI Fixes, editor scaling support

- Fixed RTNodeEditor example having no root rect and thus context menus not appearing
- Fixed broken GUI when using 2019.3+ Editor Scaling feature
- Fixed spelling mistake ForceGUIDawOffScreen -> ForceGUIDrawOffScreen in Node.cs
- Changed toolbar information, made it more compact
- Moved standard NodeEditorFramework.Standard.NodeEditorInterface to the Standard folder where it belongs

v1.0.2. GUI Fixes

Fixed missing EditorStyles in GUISkin, so errors would be thrown when EditorGUI was used in NodeInspector
Fixed EditorGUI controls using default text color and thus not fitting into the custom style by temporarily changing EditorStyles
	- Should be bugfree, critical as they can potentially mess the whole Editor GUI up
Changed RTNodeEditor to use normal EditorGUI controls when in the EditorWindow and only fall back to custom controls in play mode
Changed GUI texture properties to be consistent

LTS v1.0.1 Release package

Fixed session path in Packages crashing unity when installed through git

Difference to master:
- Exported as package for Unity Package Manager using Unity package tools
- Changed default editor path to Packages/com.seneral.nodeeditorframework

Removed unused Resource Folder

Hotfix: Removed duplicate and useless files

First clean release with all WIP stuff removed and structure improved

-> Action Node, UnityFunc and State system removed
-> removed redundancies
-> improved structure of files and nodes
-> Fixed bugs regarding for loops replaced with foreach loops