Added "SetApplicationCpuTimeLimit" and "GetApplicationCpuTimeLimit" to apt.cpp

seems simple enough

- Remove unnecessary ifdefs
- Remove commented out code. Can be retrieved later if needed.

It's unused and doesn't look like it compiles anyway :/

Instead of forcibly taking the last 4 characters, it now finds the last extension separator (the period) and takes a substr of its location.

In C++ you can simply just declare it as is.