level builder for bee

- Updated instructions in google doc, as numbers mean slightly different things for bee vs. farmer
- Bee requires two new fields - nectarGoal and honeyGoal
- Two new blocks in toolbox (get nectar and create honey)
- Fixed Karel issue where negative numbers (holes for farmer, hives for bee) were being modded by 100 when they shouldnt have been.
- Always draw path for Karel when setting initial dirt (i.e. hole/pile for farmer hive/nectar for bee).
- Changed step_modes to use the same pattern as start_directions

Let me know if looks like i missed anything/got anything wrong.