Stoper: Measure the time that a script takes to execute

This is a simple class that can measure the time that a script takes to execute.

With this class you can measure the time elapsed during:

- A complete script
- The execution of functions, loops, include files, etc..

It may be very useful to investigate how fast or slow specific parts of an application are, in order to determine the code that need to be improved to increase the performance of PHP applications