mywalls minetest mod

Adds more wall types for walls mod from minetest_game.

Walls mod comes with Minetest Game. It includes only 3 types of walls.

This mod extends it to include 19 more types.
All walls are added into the walls mod namespace and use its API.

Included in this mod walls are:

• wall for "default:brick"
• walls for:
  • "default:sandstone"
  • "default:sandstonebrick"
  • "default:sandstone_block"
• walls for:
  • "default:stone"
  • "default:stonebrick"
  • "default:stone_block"
• walls for:
  • "default:desert_stone"
  • "default:desert_stonebrick"
  • "default:desert_stone_block"
• walls for:
  • "default:desert_sandstone"
  • "default:desert_sandstone_brick"
  • "default:desert_sandstone_block"
• walls for:
  • "default:silver_sandstone"
  • "default:silver_sandstone_brick"
  • "default:silver_sandstone_block"
• walls for:
  • "default:obsidian"
  • "default:obsidian_brick"
  • "default:obsidian_block"