Removed an unnecessary line of code

When we resignFirstResponder, UIKeyboardWillHideNotification is called. If someone does a custom thing when the keyboard becomes hidden it brings problems. When we remove this line, it won't do any harm.

What do you think?
Update RETableViewBoolCell.m
Update RETableViewLongTextCell.m
Merge pull request #185 from srea/update_longtextcell

Fix RETableViewLongTextCell constraints on iOS 8
Merge pull request #183 from skrew/master

Update RETableViewBoolCell.m
Tweak example project
Version bump (1.5.12)
Update pods
Merge pull request #171 from tasomaniac/patch-1

Removed resignFirstResponder, as becomeFirstResponder is called right after it anyway.
Enabled iPhone 6 and iPhone 6 Plus screen sizes.
Fixed header and section issues on iOS 8 (due to header and footer height estimation used instead of recalculating the actual height).
Merge pull request #190 from max-horvath/ios8-fixes

Example app runs nicely on new iPhone devices, as well as some iOS 8 fixes.
Version bump (1.5.13)