Refactoring and adding check on becomeFirstResponder for placeholder visibility.
Adding initial support for attributedPlaceholders
Cleaning up indentation.
Cleaning up indentation and renaming placeholder visibility method.
Merge branch 'master' of github.com:glaszig/SZTextView

Conflicts:
	Classes/SZTextView.m
Removing similar method to togglePlaceholderViewForText:
Observe attributedText so that placeholder visibility is appropriately toggled on changes.
Changes .xcodeproj to use spaces for indentation
renaming `-togglePlaceholderViewForText` to
`-setPlaceholderVisibleForText` -- see #13
configuring initial placeholder visibility via `-becomeFirstResponder`
rather than an extra method call in `-awakeFromNib` -- #13
fixing test
adding tests for (attributed) placeholder syncing