Stackdriver Uptime Check samples (GoogleCloudPlatform#680)

* Stackdriver Uptime Check samples

* adds tests

Author: bshaffer

monitoring/composer.json

@@ -1,18 +1,24 @@
 {
     "require": {
         "symfony/console": "^3.3",
-        "google/cloud-monitoring": "^0.8"
+        "google/cloud-monitoring": "^0.11"
     },
     "autoload": {
         "files": [
             "src/create_metric.php",
+            "src/create_uptime_check.php",
             "src/delete_metric.php",
+            "src/delete_uptime_check.php",
             "src/get_descriptor.php",
+            "src/get_uptime_check.php",
             "src/list_descriptors.php",
+            "src/list_uptime_check_ips.php",
+            "src/list_uptime_checks.php",
             "src/read_timeseries_align.php",
             "src/read_timeseries_fields.php",
             "src/read_timeseries_reduce.php",
             "src/read_timeseries_simple.php",
+            "src/update_uptime_check.php",
             "src/write_timeseries.php"
         ]
     },