Improve speed, add mapping options.

v3.1.0

• Adds g:mundo_map_up_down setting.
• Adds g:mundo_auto_preview_delay setting.
• Adds validation for target buffers.
• Adds 'G' mapping to graph.
• Fix a runtime error when entering embedded terminal windows in neovim.
• Fix multiple issues associated with Mundo windows in different tabs.
• Fix default option values overriding user-set values in certain cases.
• Fix cursor initially being positioned above the graph.
• Fix some mappings not working correctly when preceded with a count.
• Fix some graph mappings moving the cursor to the target buffer.
• Fix airline plugin ignoring custom status lines.
• Fix Escape and Ctrl+c not being handled correctly in the search prompt.
• Fix MundoGetTargetState returning invalid results with some inline diffs.
• Reduced delay associated with animated playback for neovim.
• Code cleanup and refactoring.

Official plugin rename

This marks the official rename to Mundo. Documentation and commands have been renamed to reflect this change.

If you are upgrading from an older version you will need to change g:gundo settings to g:mundo, and Gundo commands to Mundo.