[ShaderSwapper] Material name inclusion and exclusion rules based resolution

[Petraller]

Added new feature to ShaderSwapper for swapping a shader to different shaders depending on the material name. Backward compatibility with old config file is maintained.

Example config file snippet:

<ShaderSwapper>
  <!-- Old structure for "Mapping" element, still supported -->
  <Mapping From="Shader Forge/main_skin" To="xukmi/SkinPlus">

  <!-- New structure for "Mapping" element, keep the old "From" attribute... -->
  <Mapping From="Shader Forge/main_skin">
    <!-- ...but introduce a "Rule" element to replace the "To" attribute -->
    <Rule Name="xukmi/SkinPlus" />
  </Mapping>

  <!-- Advanced usage, with includes and excludes -->
  <Mapping From="original_shader">
    <!-- Change to shader_0 if the material name is material_0 or material_1... -->
    <Rule Name="shader_0">
      <Include>
        <Entry>material_0</Entry>
        <Entry>material_1</Entry>
      </Include>
    </Rule>

    <!-- ...else, change to shader_1 if the material name is NOT material_2 or material_3... -->
    <Rule Name="shader_1">
      <Exclude>
        <Entry>material_2</Entry>
        <Entry>material_3</Entry>
      </Exclude>
    </Rule>

    <!-- ...else, change to shader_2 -->
    <Rule Name="shader_2" />
  </Mapping>
</ShaderSwapper>

[ManlyMarco]

Code looks good, maybe just needs some summary comments on a few methods.

The kinds of rules could be expanded a lot but it's fine if you don't want to do it for this PR.

[ManlyMarco]

@Njaecha

[Njaecha]

LGTM and back to BG3...
Jokes aside: Tested and approved!
The configuration might be a bit complicated to understand for the common Koi user though. But I don't have any improvement ideas for that except maybe a tool that helps you write the config.

[ManlyMarco]

Thanks for the PR! I guess the readme should be updated too now.