Stop explicitly supporting Node 0.10 and 0.11

package.json

@@ -45,7 +45,7 @@
     "poisson-process": "^0.2.1"
   },
   "engines": {
-    "node": ">=0.10.13"
+    "node": ">=0.12.0"
   },
   "binary": {
     "module_name": "grpc_node",

templates/package.json.template

@@ -47,7 +47,7 @@
       "poisson-process": "^0.2.1"
     },
     "engines": {
-      "node": ">=0.10.13"
+      "node": ">=0.12.0"
     },
     "binary": {
       "module_name": "grpc_node",

tools/run_tests/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=0.10.41 0.12.0 1.0.0 1.1.0 2.0.0 3.0.0 4.0.0 5.0.0
+set node_versions=0.12.0 1.0.0 1.1.0 2.0.0 3.0.0 4.0.0 5.0.0
 
 set PATH=%PATH%;C:\Program Files\nodejs\;%APPDATA%\npm
 

tools/run_tests/build_artifact_node.sh

@@ -42,7 +42,7 @@ mkdir -p artifacts
 
 npm update
 
-node_versions=( 0.10.41 0.12.0 1.0.0 1.1.0 2.0.0 3.0.0 4.0.0 5.0.0 )
+node_versions=( 0.12.0 1.0.0 1.1.0 2.0.0 3.0.0 4.0.0 5.0.0 )
 
 for version in ${node_versions[@]}
 do

tools/run_tests/distribtest_targets.py

@@ -233,5 +233,5 @@ def targets():
             NodeDistribTest('linux', 'x64', os, version)
             for os in ('wheezy', 'jessie', 'ubuntu1204', 'ubuntu1404',
                        'ubuntu1504', 'ubuntu1510', 'ubuntu1604')
-            for version in ('0.10', '0.12', '3', '4', '5')
+            for version in ('0.12', '3', '4', '5')
           ]