0.1.5

1. Enable mouse drag to adjust the position of a node.
2. Add RNA track (Exon, CDS).
3. Add annotation track from BED file.
4. Optimize layouts and add hierarchical layouts.
5. Add a menu to control the size of node.
6. Add a menu to control the linetype of edge.
7. Allow highlight multiple paths.
8. Add coordinate axis.
9. Add sequence-to-graph mapping.
10. Add node length, node sequence in 'Node information'.
11. Add 'Path information'.