1. mp.set_start_method('spawn') commented out from scripts/uncloud

2. uncloud.shared moved under uncloud.common
3. Refactoring in etcd_wrapper e.g timeout mechanism removed and few other things
4. uncloud-{scheduler,host} now better handle etcd events in their block state (waiting for requests to come)

uncloud/common/shared.py

@@ -0,0 +1,34 @@
+from uncloud.common.settings import settings
+from uncloud.common.vm import VmPool
+from uncloud.common.host import HostPool
+from uncloud.common.request import RequestPool
+from uncloud.common.storage_handlers import get_storage_handler
+
+
+class Shared:
+    @property
+    def etcd_client(self):
+        return settings.get_etcd_client()
+
+    @property
+    def host_pool(self):
+        return HostPool(
+            self.etcd_client, settings["etcd"]["host_prefix"]
+        )
+
+    @property
+    def vm_pool(self):
+        return VmPool(self.etcd_client, settings["etcd"]["vm_prefix"])
+
+    @property
+    def request_pool(self):
+        return RequestPool(
+            self.etcd_client, settings["etcd"]["request_prefix"]
+        )
+
+    @property
+    def storage_handler(self):
+        return get_storage_handler()
+
+
+shared = Shared()