Update to depend on Bukkit 1.7.2-R0.1-SNAPSHOT

This is depending on the dev build, not beta or release. The following
commits might not work on the latest dev build if the API changes before
beta.
Update data2Str() with changes from MC 1.7 (#31)

New blocks:
DIRT, SAND, LOG_2, LEAVES_2, ACACIA_STAIRS, DARK_OAK_STAIRS,
STAINED_GLASS, STAINED_GLASS_PANE, RED_ROSE, DOUBLE_PLANT

Updated blocks:
LOG, WOOD, SAPLING, WOOD_STEP, WOOD_DOUBLE_STEP, MONSTER_EGGS,
REDSTONE_COMPARATOR_OFF, REDSTONE_COMPARATOR_ON