Add option for warning on placing tile entities without entity tiles. See #689, #603, #470, #243

CraftBukkit logs and a warning and stack trace when setChunkBlockTileEntity()
is called on a block in the world which doesn't support tile entities. Vanilla
simply ignores this condition, without logging anything.

This commit adds a new configuration option to bukkit.yml, mcpc
warn-place-no-tile-entity, to switch between CraftBukkit and vanilla
behavior.

By default, this option is on (matching CB), since it can help detect
legitimate bugs where a tile entity is misplaced. But since vanilla doesn't
warn, you can set warn-place-no-tile-entity: false to reduce this log spam:

Attempted to place a tile entity ... where there was no entity tile!

See #603, #243, #303, #470, #407, #397, #596, #386, #34, #457, #689,
and #379, #153, #168, #6, #724.