src/game.js, src/components.js: Add consensus, getBaseGrid(), drawGrid(), etc.
- Add consensus sequence at top.
- Add getBaseGrid() to convert all reads into one data structure.
- Extend Read and Base components to store needed data.
- Add drawGrid() to make the grid visible (not working yet).
src/game.js: Calculate the consensus sequence from the baseGrid
src/game.js, src/components.js: update and set the consensus display
src/game.js, src/components.js: Fix bug in displaying consensus.
- Old bases weren't being destroyed.
src/game.js: Keep reads inside the game borders