BioMSA v0.1.4

Fixes and improvements to diagonal based alignment heuristic

Previously only high confidence seeds for diagonals were retained, where the seed is a common window between both sequences. In cases of sequences with low homology this proved to be not sufficient. Now all common kmers are evaluated and an optimal list of diagonals seeds is built during an extra step.
Low quality seeds (kmers that are replicated in both sequences and convey less information) are discarded which avoids combinatorial explosions
Some fixes have been made to the diagonal extension mechanism where some boundary rules were not made symmetrical between both aligned sequences