v0.0.7

Alongside the dirty modular functions, BioNick now supports node objects that can have names, branch lengths and connections to other node objects. A set of node objects can be represented as a tree object. A newick class was also added to hold newick string instances.
A Neighbor-Joining algorithm was implemented to work with distance matrices. Neighbor joining output can be parsed as a tree object and exported as a newick string.