Update success code

[congwang09]

Relates to: #340

Update the success code. It seems that all the 4xx codes will be propagated from pce.

[YufengXin]

@congwang09 for successful place_connection, PCE still returns a '200', not '201'

[coveralls]

Pull Request Test Coverage Report for Build 11524874793

Details

• 4 of 9 (44.44%) changed or added relevant lines in 2 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage decreased (-0.04%) to 56.777%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
sdx_controller/controllers/l2vpn_controller.py	2	4	50.0%
sdx_controller/handlers/connection_handler.py	2	5	40.0%

Files with Coverage Reduction	New Missed Lines	%
sdx_controller/controllers/l2vpn_controller.py	1	66.67%

Totals
Change from base Build 11501191846:	-0.04%
Covered Lines:	1110
Relevant Lines:	1955

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💛 - Coveralls

[congwang09]

@congwang09 for successful place_connection, PCE still returns a '200', not '201'

Sounds good. Updated to use generic checking, e.g., 200-299 are all success.

[YufengXin]

@congwang09 Could you also produce 402, 409, 410 codes in connection_handler.py?

1. When the the traffic_matrix returned from pce is Noe, return code 402.
2. When the solution returned from the pce solver is none, it should return a 410
3. pce.generate_connection_breakdown() now raises exceptions w/ error code (now 409), when you catch it, pls return it.

Now they all return 400.

400 is returned when the body is not proper json, returned by Swagger already.