Add stairs support [GitHub#38][GitHub#17] [Patch by @nanobowers]

Add block canvas support [GitHub#39][GitHub#19] [Patch by @nanobowers]

Add stemplot support [GitHub#40][GitHub#30] [Patch by @nanobowers]

Add an example of animation [GitHub#33] [Patch by @mrkn and @kojix2]

Fix interpolation bug of lineplot [GitHub#37][GitHub#32] [Patch by @nanobowers] [Reported by @Nakilon]

Support color: option in render method [GitHub#45]

Add canvas_types method [GitHub#44][GitHub#42] [Reported by @kojix2]

Use appropriate message for invalid border types, and add border_types method [GitHub#43][GitHub#41] [Reported by @kojix2]