1.8:    1.8.7-p374
1.8.7:  1.8.7-p374
1:      1.9.3-p448
1.9:    1.9.3-p484
1.9.3:  1.9.3-p484
2:      2.0.0-p353
2.0:    2.0.0-p353
2.0.0:  2.0.0-p353
2.1:    2.1.0-preview2
2.1.0:  2.1.0-preview2
stable: 2.0.0-p353

1.8:    1.8.7-p374
1.8.7:  1.8.7-p374
1:      1.9.3-p448
1.9:    1.9.3-p484
1.9.3:  1.9.3-p484
2:      2.0.0-p353
2.0:    2.0.0-p353
2.0.0:  2.0.0-p353
2.1:    2.1.0-rc1
2.1.0:  2.1.0-rc1
stable: 2.0.0-p353

Update Ruby 2.1 to ruby-2.1.0-rc1.
Update Ruby 2.1 to ruby-2.1.0-rc1.
