Minecarts always spawn facing east/west and move upward slightly when being placed on rails

The Bug:

Minecarts always spawn facing east/west and move upward slightly when being placed on rails.

Steps to Reproduce:

1. Place a minecart on a rail that's facing north or south.
2. Watch the minecart closely.

Observed Behavior:

Minecarts always spawn facing east/west and move upward slightly when being placed on rails.

Expected Behavior:

Minecarts would spawn facing the correct direction and not move upward slightly when being placed on rails.