chore: repo maintenance + no path dependencies (#991)

- Move `tokio` into its own directory.
- Remove `path` dependencies.
- Run tests with once with crates.io dep and once with patched dep.

tokio-timer/Cargo.toml

@@ -20,7 +20,7 @@ Timer facilities for Tokio
 
 [dependencies]
 futures = "0.1.19"
-tokio-executor = { version = "0.1.1", path = "../tokio-executor" }
+tokio-executor = "0.1.1"
 crossbeam-utils = "0.6.0"
 
 # Backs `DelayQueue`
@@ -29,4 +29,4 @@ slab = "0.4.1"
 [dev-dependencies]
 rand = "0.6"
 tokio-mock-task = "0.1.0"
-tokio = { version = "0.1.7", path = "../" }
+tokio = "0.1.7"