Implement non-compressed block_collection class.
Move the freespace_collection class into its own file.
Add an additional constructor to the block_collection class.
Add block collection unit test.
Add initial_configuration method to freespace_collection.
Fix alloc method in freespace_collection.
Fix get_configuration method in freespace_collection.
Make block_collection open files in r/w mode.
block_collection::free_block now truncates files.
Fix block_collection:write_block.
Add erase unit test for block_collection.