Limit use of advance monitors for loading

[Christian-B]

test show that for small content the Advanced Monitors are actually worse.

Limited testing showed
for very small data (under 100 bytes) Advance Monitors where very poor
for very large data (over 100,000 bytes advance monitors where much faster)
12800 bytes 50 packets appears a reasonable toggle point

There is a cfg disable_advanced_monitor_usage_for_data_in
But that is an all or nothing approach

This PR automatically switches between the 2 strategies.

If No ds regiond's content is larger than the cutoff
EDIT: Fixed routes are still created, loaded and reported. But the report now has a cfg flag False by default

Python

• Router timeouts are not changed
• Simple load is used everywhere
  Java
• called as if disable_advanced_monitor_usage_for_data_in was true
• No Java code change needed

If one or more content is larger
Python
Router timeouts are created
For each content the choice is made which to use
Java
For each content the choice is made which to use
See:

Must be done at the same time as:
SpiNNakerManchester/sPyNNaker#1472

Tested by:
SpiNNakerManchester/sPyNNaker#1472
SpiNNakerManchester/IntegrationTests#281