
---- Read the text file "bragg_events.txt" ----

The file contain a sequence of events, and for each event:
- an integer identifier,
- a number of energy measurements,
- a list of integer numbers corresponding to the energy loss.

***
Create an "Event" struct, with members corresponding to the data
listed above.

***
Create a function "read" taking as argument an input file stream,
reading an event and returning a pointer to the event or zero 
at the file end.

***
Create a function "dump" taking as argument a const-pointer to event
and printing a dump on the screen.

***
Create a function "clear" deleting the event and its content.

***
Create a "main" function reading the file and calling the 
dump and clear functions.

********* final list of functions *********

main                   to do
struct Event           to do
read                   to do
clear                  to do
dump                   to do
