Implemented basic input function and tested for the three test cases
Added unittests and made style changes
Merge branch 'master' of https://github.com/kexinrong/NetworkSimulator into Input
Changed case_i to CASE_i
Fixed case_i to CASE_i everywhere
(I had missed some last time)
Merge pull request #5 from kexinrong/Input

Implemented basic input function and tested for the three test cases