v0.21.2

Added

• add convenience fns: out_dir and out_dir_path to the build script.
• add new build::utils module.

Changed

• move build codegen output from /build/out/ to {OUT_DIR}/build/.
• show debug information about OUT_DIR and the code-generated files.
• move println to the utils module.
• update .gitignore.

Fixed

• this should fix compilation in docs.rs.

Full Changelog: v0.21.1...v0.21.2