[v2] use binary fields in block_store table

[arvidn]

This patch updates the v2 database schema to use binary fields instead if hex in the block_store table. This reduces the size of the table a little bit. Most of this table is made up of serialized clvm code, which is already stored as binary.

These changes are best reviewed hiding white space changes.

test	v1	v2	v2 / v1
table size	2420 MB	2413 MB	99.7%

This change in size may seem insignificant relative to the size of the change. however, most of the code change is mostly related to making any distinction between v1 and v2, and there are more significant changes to be made where it's required to distinguish v1 from v2.