New visual changes released with 0.1.0

I've slowly working on the new visual update due to daily life things, but I've made available my first iteration of the basalt cavern theme, I'm still playing with lighting and other small details. I'm aiming for the new update to add a start menu and move the pause to the esc key, as well make the background landscape fully procedurally generated, as now it's a mix of pre-generated meshes and a small pick of procedural generation.

Changelog: 

• Introduces basalt cavern theme.