remove extraneous call to addConstraints.
Fix unbalanced called to begin/end appearance selectors in some cases.
Re-type property.
Merge pull request #117 from Raizlabs/bugfix/zeveisenberg/fix-unbalanced-appearance-calls

Fix unbalanced called to begin/end appearance selectors
Merge pull request #115 from Raizlabs/bugfix/eslosser/remove-extraneous-addconstraint

remove extraneous call to addConstraints.
avoid a hang on 5s and older when scrolling and using section views.
Merge branch 'bugfix/eslosser/fix-hang-while-scrolling' into bugfix/arrouse/Warnings