Multiple k-mer sizes bug

[dkoslicki]

Current implementation of multiple k-mer size containment index computation may have some bugs in it as noted here. In particular, training with 30-60-10 and training with 60-60-10 results in different 60-mer containment index values (which it shouldn't).

[dkoslicki]

This is addressed in c8c91f4, but leaving open until we get a more complete testing environment open as per #14 as only checked with local testing.

[dkoslicki]

Closing as some testing is done, and more testing is being implemented in #14