Refactored CityConnect.cpp and CityConnect.h

CityConnect.cpp:
- Line 60: removed unnecessary integer command
- Line 172, 177: removed duplicate return statements.
- Function int CityConnect::getPositionOfExistingRoute: Modified if
condition such that only need to return NOT_FOUND once.

CityConnect.h:
- Removed <algorithm> and <stdio.h>
- Merged both public: sections in the class.
Refactored CityConnect.cpp

Line 185 & 251: converted to int-only comparison
Line 256: Condensed if condition