Make sure that imports are always in the same order between runs. This

makes the output more stable for putting it into a versioning system
like git

libjrpc/src/targets/rust.rs

@@ -1,6 +1,6 @@
 use anyhow::Result;
 use log::warn;
-use std::collections::{HashMap, HashSet};
+use std::collections::{BTreeMap, BTreeSet};
 
 use crate::compile::{Compile, CompileContext, FileGenerator};
 use crate::ir::{BaseType, EnumDefinition, ServiceDefinition, Step, Type, TypeDefinition};
@@ -46,7 +46,7 @@ impl RustCompiler {
     fn add_dependencies(
         &mut self,
         file: &mut FileGenerator,
-        depends: &HashSet<BaseType>,
+        depends: &BTreeSet<BaseType>,
     ) -> Result<()> {
         for dep in depends {
             match dep {
@@ -409,7 +409,7 @@ impl RustCompiler {
 }
 
 impl Compile for RustCompiler {
-    fn new(options: &HashMap<String, String>) -> anyhow::Result<Self> {
+    fn new(options: &BTreeMap<String, String>) -> anyhow::Result<Self> {
         let crate_name = if let Some(crate_name) = options.get("rust_crate") {
             crate_name.to_string()
         } else {