Add version info to build

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "libfj"
-version = "0.7.3"
+version = "0.7.4"
 authors = ["NGnius (Graham) <ngniusness@gmail.com>"]
 edition = "2018"
 description = "An unofficial collection of APIs used in FreeJam games and mods"

src/lib.rs

@@ -15,3 +15,5 @@ pub mod techblox;
 pub mod convert;
 #[cfg(feature = "robocraft2")]
 pub mod robocraft2;
+
+pub const VERSION: &str = env!("CARGO_PKG_VERSION");