Add an option for suppressing the blank lines between sections.

The setting is stored in the negative (“no blank line between sections”) so that the default state for existing users is to be on, thus no behavior change. When switched on, VVBaseCommenter’s emptyLine is just an empty string.

Also updated VVDocumenterSetting to use @property instead of manually declaring getters and setters.
Style cleanup after last commit.
One more fix, somehow the action got disconnected in a rename.
Removed blank line.
Fixed ib->.m button hookup and reset to defaults.

I'm new to this whole xcode thing :)
Merge pull request #39 from NoahRic/master

Add option to suppress blank lines between sections