Count out unnecessary but error causing tests

Added those tests with nosetest 'exclude' option. '--config=setup.cfg'
is also required when run_test.sh.
Fix unittest errors and failures

1. Fix DuplicateOption error on dhcp_agent and security_groups_rpc
   with 'CONF.root_helper'
2. Fix metadata_agent test_report_state failure and removed not
   applicable test with Grizzly
Fix testcase 'test_create_subnet_with_two_host_routes' failed

Fix bug 1179348

Change-Id: I0cd5d303da0f394cec173aeee52efcd337282c94
Signed-off-by: Christoph Thiel <c.thiel@telekom.de>
Fix testcase 'TestPortsV2.test_range_allocation' failed randomly

Fix bug 1179370

Change-Id: Id5645546c98549c9d7cf68359e0f6fa128ad84b7
Signed-off-by: Christoph Thiel <c.thiel@telekom.de>
Skip test_db_plugin:test_no_more_port_exception

NG allows port creation with /32 subnet, so this test case will
not work as expected.
Remove port ID from dhcp device ID

Dhcp device ID originally includes port ID, but we removed it to
make dhcp listen & gateway IP the same at all cnodes to short
live migration time.
Add 'option:netmask,255.255.255.255' to dnsmasq opt

To give VM with /32 subnet IP, 'option:netmask,255.255.255.255' this
option was added to dnsmasq opt file.
Add metadata_network config option

metadata_network config added to provide isolated metadata network
when enable_namespaces=False, which is NG case.
Merge pull request #32 from hyunsun/UCLOUDNG-1397

UCLOUDNG-1397: make quantum unit test passed in python unittest