merging lsm and srb layer, new layer - packers

object_keeper now is keeping fragments any size, deep refactored and
supported log write and read explicitly.
packer - layer under object_keeper and responds by working on stored data
structures, them updating and extrating, merging, divergind and etc. For each
type structure - pack_type and packer. For exapmple - json packer
storage now is more ligthwise front end. Backends now is commonjs modules.
Common work doing in backends