Don't override empty-paren methods as paren-less.

An exception is made for toString.
Be explicit about empty param list calls.

With the exception of toString and the odd JavaBean getter.
Banish needless semicolons.
Reorder to avoid code appearing like a forward reference.

It isn't, because LOOP_HEADER and friends are compile time
constants. But I'd argue that its clearer not to rely on that here.
More explicit empty paren lists in method calls.
Fix two malformed format strings.
Remove redundant 'val' from case class params.
Don't wrap an array just to get its length.

Use .length directly, avoiding the allocation of the WrappedArray.
Remove redundant explicit returns.
Modernize legacy backquotes in comments.

Was: ``blah''
Now: `blah`
Address some Scaladocrot

 - @param tags whose name drifted from the corresponding parameter
 - Remove or complete a few stray stub comments (@param foo ...)
 - Use @tparam where appropriate.
Merge pull request #2165 from retronym/topic/empty-paren

Spring cleaning