Fix timings so that when linking a process within a process the linked process retains only it's time

When creating process 1, 2 and 3 and a timing is made on each process and I then link Process 1 to Process 2 in Process 2 and then 2 to 3, Currently when linking process 1 to 2, process 2 has an aggregated time of Process 2 and 3 and then if process 2 is linked to 3 process 2 carries over the time taken for both process 1 and 2. This amount gets confusing when it is a mega process with many processes. Solution would be to provide actual individual process time and show these aggregated time when creating a Process Overview in the Group folder that contains the mega process