reorganize into separate crates

- taskchampion -- core implementation of a replica
 - taskchampion-cli -- command-line interface
 - taskchampion-sync-server -- server implementation (not much yet!)

sync-server/Cargo.toml

@@ -0,0 +1,9 @@
+[package]
+name = "sync-server"
+version = "0.1.0"
+authors = ["Dustin J. Mitchell <dustin@mozilla.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]