Add editorconfig

This commit also purges .gitignore, since the files mentioned in it
should be handled by global ignore file.

Fixes #4378.

.editorconfig

@@ -0,0 +1,18 @@
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+trim_trailing-whitespace = true
+insert_final_newline = true
+
+[*.{glsl,rs,toml}]
+indent_style = space
+indent_size = 4
+
+[*.yml]
+indent_style = space
+indent_size = 2
+
+[Makefile]
+indent_style = tab

.gitignore

@@ -1,36 +1 @@
-# Rust build directory
+target
-**/target
-
-# Rust subcrate lockfiles
-*/Cargo.lock
-
-# Temp files
-.idea
-.vscode
-*.iml
-*~
-
-# vim temporary files
-*.swp
-
-# other ignores
-*.DS_Store
-=======
-
-# Snapcraft files
-stage
-prime
-parts
-*.snap
-*.pyc
-alacritty_*_source.tar.bz2
-
-# WiX files
-/Wix.3.11.1
-*.msi
-*.wixobj
-*.wixpdb
-
-# Perf tools
-perf.data*
-flamegraph.svg