Copy angular-socket-io-seed.

Unreviewed.

Github URL:
    https://github.com/btford/angular-socket-io-seed

HEAD:
    https://github.com/btford/angular-socket-io-seed/commit/cb5f0d1254609dc571f2051ce659407f9f4147ab
Merge branch 'master' of github.com:JinGyeong-Jeong/Challengers3 into smksyj
Merge branch 'smksyj' of github.com:JinGyeong-Jeong/Challengers3 into smksyj
added controller for problem list