Some tweaks to blocks.
Some tweaks to blocks.

Default list indexing to 1, not 0, since 0 is not a valid value
Move list append up further in the tray.

google/codeworld,alphalambda/codeworld,pranjaltale16/codeworld,pranjaltale16/codeworld,alphalambda/codeworld,google/codeworld,pranjaltale16/codeworld,alphalambda/codeworld,google/codeworld