Upgrade alembic to 0.8.4
Upgrade alembic to 0.8.4

wlonk/warehouse,pypa/warehouse,dstufft/warehouse,wlonk/warehouse,dstufft/warehouse,wlonk/warehouse,karan/warehouse,alex/warehouse,pypa/warehouse,alex/warehouse,dstufft/warehouse,karan/warehouse,karan/warehouse,alex/warehouse,alex/warehouse,pypa/warehouse,karan/warehouse,karan/warehouse,alex/warehouse,dstufft/warehouse,pypa/warehouse