Extract method
Use ruby tree to store map internally
Add MindmapTreeNode
Add mindmap_tree_node
Recognize and handles JIRA nodes
Can add nodes to any node
Jiramap uses new mindmap_tree instead of of mindmap class
Remove unused code
Add legend nodes to map
Fix style attribute for new issues
Do not create Uncategorized or Legend if it exists
Refactor jiramap-file
Update README with settings-file instructions
Configure customfield 'sprint'
Add parameter for output-filename
Update README