Removes redundant code in quantum.api.api_common

Fixes bug #1102313

Change-Id: Ie321c48ae6d38f013e1ef8471df4d86b63b28931
Merge "Removes redundant code in quantum.api.api_common"
make IPv6 unit test work on systems with eth0

fixes bug 1103074

The link local unit test was failing because it depended on eth0 to
exists.  This mocks getaddrinfo() to ensure a consistent return value
across testing environments.

Change-Id: Ie1a4d837efcacac8c8d2217c164ad751922e1a5f
Merge "make IPv6 unit test work on systems with eth0"