Remove Graph::getVertexFirst()
Update references to Graph::getVertexFirst()
Remove Walk::getVertexSource() and Walk::getVertexTarget()
Fix invalid reference to Vertices::getVertexFirst()
Rename isDirected() to hasDirected() and add hasUndirected(), isMixed()
Update references to hasDirected()
Add tests for Algorithm\Directed (100% coverage)
Update reference to Directed::hasDirected()
Add Algorithm\Directed to CHANGELOG
Add missing backtick
Add failing test for multiple components
Add (failing) tests to detect negative cycles
Improve error handling when constructing incomplete cycles
Test constructing loops / cycles (100% coverage)
Add tests for connected components (100% coverage)
Merge pull request #80 from clue/directed

Rename Algorithm\Directed::isDirected()
Merge remote-tracking branch 'origin/master' into walk
Add new Walk behavior to CHANGELOG
Merge remote-tracking branch 'origin/test-connectedcomponents'
Merge branch 'master' into remove-graph-getvertexfirst