eliminate cet usage in destinator, igo8, mmo. (#463)

eliminate cet usage in destinator, igo8, mmo. (#463)

* eliminate cet usage in igo8 format.

added test to verify written header.
This test requires spaces to be embedded within option strings.
testo had to be modififed to preserve these embedded spaces.

* eliminate cet usage in destinator.

* eliminate cet usage in mmo.

This also fixes some apparent encoding/decoding bugs, although
our understanding of this binary format is likely incomplete.

* use smart pointer with encoders/decoders.

* fix bad resolution of merge conflict.