Add support for Tmpfs declaration in Hostconfig.

This adds support for the Tmpfs option introduced in Docker 1.10.
See: https://github.com/docker/docker/pull/13587

Signed-off-by: Jan Losinski <losinski@wh2.tu-dresden.de>

docker/utils/utils.py

@@ -337,6 +337,33 @@ def convert_volume_binds(binds):
     return result
 
 
+def convert_tmpfs_mounts(tmpfs):
+    if isinstance(tmpfs, dict):
+        return tmpfs
+
+    if not isinstance(tmpfs, list):
+        raise ValueError(
+            'Tmpfs spec must be a list'
+        )
+
+    result = {}
+    for mount in tmpfs:
+        if isinstance(mount, six.string_types):
+            if ":" in mount:
+                name, options = mount.split(":", 1)
+            else:
+                name = mount
+                options = ""
+
+        else:
+            raise ValueError(
+                "Tmpfs spec have to be str, unicode or tuple"
+            )
+
+        result[name] = options
+    return result
+
+
 def parse_repository_tag(repo_name):
     parts = repo_name.rsplit('@', 1)
     if len(parts) == 2:
@@ -584,7 +611,7 @@ def create_host_config(binds=None, port_bindings=None, lxc_conf=None,
                        mem_limit=None, memswap_limit=None, mem_swappiness=None,
                        cgroup_parent=None, group_add=None, cpu_quota=None,
                        cpu_period=None, oom_kill_disable=False, shm_size=None,
-                       version=None):
+                       version=None, tmpfs=None):
 
     host_config = {}
 
@@ -751,6 +778,9 @@ def create_host_config(binds=None, port_bindings=None, lxc_conf=None,
 
         host_config['CpuPeriod'] = cpu_period
 
+    if tmpfs:
+        host_config["Tmpfs"] = convert_tmpfs_mounts(tmpfs)
+
     return host_config