Previously, when the cursor was hover a CPTextField the cursor was an arrow till we selected the textField.
Now when the cursor is hover a CPTextField, and if this textField is enabled and editable or selectable we show the selecting cursor. This is the default behavior in Cocoa as well.
Updated manual test Tests/Manual/CPTextField/
Previously _CPThemeAttribute had an ivar called _parentAttribute, which represented the attribute from the theme descriptor, as opposed to the attribute for a particular instance of a view.
This commit renames that ivar to _themeDefaultAttribute, so it is clearer where it gets its values.