enforce intial 1:1 selection aspect ratio for square & circle selection types, as suggested by @paulflo150 in issue #6
refactor area type checking to use new getter method rather than passing around the type; improvements to suggestion by @paulflo150 in issue #6
* refactor area type getter down to area classes, with a wrapper method in the crop host class
* enforce 1:1 aspect ratio for square-like selections when attemping to drag out of bounds
Merge remote-tracking branch 'origin/master' into 0.2.1
add updated build products