Drop support for io.js, fix minor issue with node extension

package.json

@@ -52,7 +52,7 @@
     "poisson-process": "^0.2.1"
   },
   "engines": {
-    "node": ">=1.1.0"
+    "node": ">=4"
   },
   "binary": {
     "module_name": "grpc_node",

src/node/ext/server_uv.cc

@@ -47,12 +47,12 @@ namespace grpc {
 namespace node {
 
 using Nan::Callback;
+using Nan::MaybeLocal;
 
 using v8::External;
 using v8::Function;
 using v8::FunctionTemplate;
 using v8::Local;
-using v8::MaybeLocal;
 using v8::Object;
 using v8::Value;
 

templates/package.json.template

@@ -54,7 +54,7 @@
       "poisson-process": "^0.2.1"
     },
     "engines": {
-      "node": ">=1.1.0"
+      "node": ">=4"
     },
     "binary": {
       "module_name": "grpc_node",

tools/run_tests/artifacts/build_artifact_node.bat

@@ -27,7 +27,7 @@
 @rem (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 @rem OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-set node_versions=1.1.0 2.0.0 3.0.0 4.0.0 5.0.0 6.0.0 7.0.0
+set node_versions=4.0.0 5.0.0 6.0.0 7.0.0
 
 set electron_versions=1.0.0 1.1.0 1.2.0 1.3.0 1.4.0
 

tools/run_tests/artifacts/build_artifact_node.sh

@@ -42,7 +42,7 @@ mkdir -p artifacts
 
 npm update
 
-node_versions=( 1.1.0 2.0.0 3.0.0 4.0.0 5.0.0 6.0.0 7.0.0 )
+node_versions=( 4.0.0 5.0.0 6.0.0 7.0.0 )
 
 electron_versions=( 1.0.0 1.1.0 1.2.0 1.3.0 1.4.0 )