refactor RotateTransform tests for a given a center point
add 'point' value in fixture for RotateTransform
Add 'point' input for RotateTransform center
Add case for 'point' for a defined point on the plane
RotateTransform rotates per a given center point: closes #67
Merge branch 'development' into staging
Merge branch 'staging' of github.com:jahan-addison/gridpaste into staging