cloudinit.net: add network config v2 parsing and rendering

Network configuration version 2 format is implemented in a package
called netplan (nplan)[1] which allows consolidated network config
for multiple network controllers.

- Add a new netplan renderer
- Update default policy, placing eni and sysconfig first
  This requires explicit policy to enable netplan over eni
  on systems which have both (Yakkety, Zesty, UC16)
- Allow any network state (parsed from any format cloud-init supports) to
  render to v2 if system supports netplan.
- Move eni's _subnet_is_ipv6 to common code for use by other renderers
- Make sysconfig renderer always emit /etc/syconfig/network configuration
- Update cloud-init.service systemd unit to also wait on
  systemd-networkd-wait-online.service

1. https://lists.ubuntu.com/archives/ubuntu-devel/2016-July/039464.html

1 files changed, 9 insertions, 0 deletions

diff --git a/cloudinit/util.py b/cloudinit/util.py
index 82f2f76b..33019579 100644
--- a/cloudinit/util.py
+++ b/cloudinit/util.py
@@ -2373,4 +2373,13 @@ def system_is_snappy():
         return True
     return False
 
+
+def indent(text, prefix):
+    """replacement for indent from textwrap that is not available in 2.7."""
+    lines = []
+    for line in text.splitlines(True):
+        lines.append(prefix + line)
+    return ''.join(lines)
+
+
 # vi: ts=4 expandtab