Is it planed that droids will be upgrade-able,
forinstance let's say I have a Battledroid,
now (after R&D) the TF has created a upgrade
chip that boosts the Projectile Weapons stat
of the Battledroid to 2.

Basicly, Im asking if moddifying your droid after
it is created is planned.

Modifying any entity will apply to the same rules for modifying, which aren't done yet. You will most likely be able to modify your droid, however there is no set of rules available that determines in what way you will be able to modify it.