Preparing code for next change
When pruning, do not remove parents with a single child, unless some of their children were removed
Merge pull request #11 from fangly/master

Pruning without removing nodes with single child that were already in tree
Merge branch 'master' of github.com:rvosa/bio-phylo
added deroot() method, which collapses one of the interior children of a bifurcating root to obtain a basal trichotomy
added _Inline folders to .gitignore
added merging constructor to project class