Add "Number of Trees per species" validation in the Batch Form

[NicolasDontigny]

In the Batch Form, we need to make some modifications to the field "Number of Trees per Species". It should only display the species selected in the parent site, with an indication of how many trees are available in each.

The number of trees available is equal to:
[Total number of trees of that species in the parent site] - [Sum of all number of trees of that species in the other batches from that site]

The user should not be able to add more than the number of trees available for each species