Refactor scheduler server

ballista/rust/client/src/context.rs

@@ -75,7 +75,7 @@ impl BallistaContextState {
 
         log::info!("Running in local mode. Scheduler will be run in-proc");
 
-        let addr = ballista_scheduler::new_standalone_scheduler().await?;
+        let addr = ballista_scheduler::standalone::new_standalone_scheduler().await?;
 
         let scheduler = loop {
             match SchedulerGrpcClient::connect(format!(

ballista/rust/scheduler/scheduler_config_spec.toml

@@ -27,9 +27,9 @@ doc = "Print version of this executable"
 [[param]]
 abbr = "b"
 name = "config_backend"
-type = "ballista_scheduler::ConfigBackend"
+type = "ballista_scheduler::state::ConfigBackend"
 doc = "The configuration backend for the scheduler, see ConfigBackend::variants() for options. Default: Standalone"
-default = "ballista_scheduler::ConfigBackend::Standalone"
+default = "ballista_scheduler::state::ConfigBackend::Standalone"
 
 [[param]]
 abbr = "n"

ballista/rust/scheduler/src/api/handlers.rs

@@ -10,7 +10,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use crate::SchedulerServer;
+use crate::scheduler_server::SchedulerServer;
 use ballista_core::serde::{AsExecutionPlan, AsLogicalPlan};
 use ballista_core::BALLISTA_VERSION;
 use warp::Rejection;

ballista/rust/scheduler/src/api/mod.rs

@@ -12,7 +12,7 @@
 
 mod handlers;
 
-use crate::SchedulerServer;
+use crate::scheduler_server::SchedulerServer;
 use anyhow::Result;
 use ballista_core::serde::{AsExecutionPlan, AsLogicalPlan};
 use std::{