[partio4Maya] Find a way to work with very big cache in Maya viewport

[dhaguenauer]

A very big cache could be for instance a 4Gb/frame.

On our workstations each loading when scrubing can take in this case 45 sec when scrubbing the timeline which is quite problematic in term of interactivity for the users.

Here is a hack, yet fonctionnal, to skip a certain percentage of .bhclassic particle from loading.

https://github.com/mikrosimage/partio/tree/mikros
commit [Partio4Maya] add a skip load feature (WIP: very ugly hack on lib/io … (11c4e73)