update submodule, module version

Author: vaaaaanquish

.gitmodules

@@ -1,5 +1,5 @@
 [submodule "xgboost-sys/xgboost"]
 	path = xgboost-sys/xgboost
-	url = git@github.com:davechallis/xgboost
+	url = https://github.com/davechallis/xgboost
 	branch = v0.80-modified
 	ignore = dirty

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "xgboost"
-version = "0.1.4"
+version = "0.2.0"
 authors = ["Dave Challis <[email protected]>"]
 license = "MIT"
 repository = "https://github.com/davechallis/rust-xgboost"
@@ -10,7 +10,7 @@ documentation = "https://docs.rs/xgboost"
 readme = "README.md"
 
 [dependencies]
-xgboost-sys = { path="./xgboost-sys" }
+xgboost-sys = "0.2.0"
 libc = "0.2"
 derive_builder = "0.5"
 log = "0.4"