support for new figures

[dcmorse]

• [x] gentlespoons/ladles star_promenade [rotations] http://contradb.com/dances/26
• [x] partner/neighbor butterfly_whirl [rotations] http://contradb.com/dances/26
• [x] gyre star [rotations]
• [x] roll away
• [x] roll away with half sashay? c.f. http://contradb.com/dances/39
• [x] cross_trails c.f. http://contradb.com/dances/39

[dcmorse]

• [x] Contra Corners

[dcmorse]

https://en.wikipedia.org/wiki/Contra_dance_choreography

[dcmorse]

• [x] Mad Robin - was there already, but rotation support was added
• [x] Dixie Twirl - for a line-of-four - exciting!

Swinging Star - proposed but rejected -- it's just another hand grip for star-left.

[dcmorse]

• [x] uh (gents/ladles) to long wavy line