* designs are now using the construction time var and the hacky /obj/item/mechavars is gone
* designs updated : there shouldn't be "no material" designs anymore
* cleaned the objects of their construction_cost and construction_time vars
* fixes the material name being displayed with $ character before
* this also fixes the overlay animation in inserting sheets
* the category var is now a list, so parts can be build/used with several chassis (fixes the Firefighter Chassis appearing when building Ripley)
* properly fix the href vulnerability when emptying (you can now remove all sheets of a materiel at once)
* the exofab now won't create a material sheet if there's not enough material (e.g 1000 metal)
* the exofab now won't accept a sheet if it would overstuff it (losing some material in the process)
* cleaned the code a bit (simplified, streamlined, using global vars, etc)
Finish #5722 and fixes#5954.
adds 3 new types of shotgun ammo. make them by crafting the special shell in RND, and then using table-crafting to make the unique ammo.dmi
meteorshot, made with compressed matter cartridges
pulse slugs, shotgun rounds with the properties of a laser weapon.
dragonsbreath rounds, area-of-effect flame weapons.
renames ammunition/bullets.dm to ammunition/ammo_casings.dm, which is more accurate
splits RND designs up into their own files
