proton-builder: add more information in readme file

Signed-off-by: Carlo Dandan <carlodandan.personal@proton.me>

README.md

@@ -1,2 +1,12 @@
-## (Work/Update in Progress)
-Github Action for Compiling Kernel from Source using Proton Clang
+### Action Kernel Builder | Proton
+Compile your first custom kernel using [proton-clang](https://github.com/kdrag0n/proton-clang).
+
+### Toolchain/Compiler Version
+* Clang+LLVM (v13.0.0, as of commit [b4fd512c](https://github.com/llvm/llvm-project/commit/b4fd512c36ca344a3ff69350219e8b0a67e9472a))
+* Binutils (v2.36.1, trimmed)
+
+### Builder Notes
+* The last proton-clang release is the current branch, `master`. If you want to build with much older release, choose your own tag.
+* The builder uses antman from [neutron-clang](https://github.com/Neutron-Toolchains) to patch glibc incase clang requires v2.36+ in compiling, since the default glibc package from Debian/Ubuntu (latest, in gitaction) were at 2.35 only.
+* To change invocations for make command, just edit make.txt, change it how ever you want.
+* Builder uses osm0sis' AnyKernel3 template but with modified (just a bit) anykernel.sh - device checking were set to 0. Flash at your own risk.