Split the server into three crates (#56)

This will make it easier to build variations on the server, or embed it
into larger projects.

server/Cargo.toml

@@ -0,0 +1,26 @@
+[package]
+name = "taskchampion-sync-server"
+version = "0.4.1"
+authors = ["Dustin J. Mitchell <dustin@mozilla.com>"]
+edition = "2021"
+publish = false
+
+[dependencies]
+taskchampion-sync-server-core = { path = "../core" }
+taskchampion-sync-server-storage-sqlite = { path = "../sqlite" }
+uuid.workspace = true
+actix-web.workspace = true
+anyhow.workspace = true
+thiserror.workspace = true
+futures.workspace = true
+serde_json.workspace = true
+serde.workspace = true
+clap.workspace = true
+log.workspace = true
+env_logger.workspace = true
+chrono.workspace = true
+
+[dev-dependencies]
+actix-rt.workspace = true
+tempfile.workspace = true
+pretty_assertions.workspace = true