Adding support for RDB version <= 12 and refactoring

.gitignore

@@ -1,6 +1,17 @@
-/target
-/Cargo.lock
-/utils/pkg
-/utils/src
-/utils/rdb-rs
-*.tar.gz
+# Generated by Cargo
+# will have compiled files and executables
+debug/
+target/
+
+# Remove Cargo.lock from gitignore if creating an executable, leave it for libraries
+# More information here https://doc.rust-lang.org/cargo/guide/cargo-toml-vs-cargo-lock.html
+Cargo.lock
+
+# These are backup files generated by rustfmt
+**/*.rs.bk
+
+# MSVC Windows builds of rustc generate these, which store debugging information
+*.pdb
+
+# Python
+.python-version