Add decorator expected_errors for security_group extension

This patch add decorator expected_errors for all the APIs of
security_group that required by v2.1 API.

Partially implements blueprint v2-on-v3-api

Change-Id: I6ccf9f3b7d7137948d16481d82d00220a27d8541
Fix the cell API with string rpc_port failed

When cell create/update accept rpc_port as string, it will
return 500. This patch add code to covert the string as integer.

Change-Id: I8ace46731ac02f810b978c54843b6e137c9882be
Closes-Bug: #1389933
Limit tcp/udp port to be empty string in json-schema

tcp/udp port can be string and integer. Currently the json-schema accept
string, but it didn't limit the length of string, so there can be pass
emtpy string as tcp/udp port. This patch add string length limit to it.

Change-Id: I6c338a2417ae5f8817b24823b3d745dc1e0fbd58
Cleanup v2.1 controller inheritance

For microversions support to work all the API controllers must
inherit from wsgi.Controller rather than object. Currently most
do inherit from wsgi.Controller but some don't. This patch
ensures that all do so.

Partially implements blueprint api-microversions

Change-Id: Ic7351298ae96aa7bb509eb3784e672d5feea262a
Merge "Add decorator expected_errors for security_group extension"
Merge "Fix the cell API with string rpc_port failed"
Merge "Limit tcp/udp port to be empty string in json-schema"
Merge "Cleanup v2.1 controller inheritance"