Smart Line Break Converter

The smartlinebreakconverter will selectively apply the line break converter filter (in the core filter module) based on whether it thinks it's necessary. This in particular resolves an issue we have with users copying/pasting content into TinyMCE and having extraneous line breaks hidden in the content. Basically, if it appears the content has line breaks in it coded with HTML (as from a WYSIWYG editor), then it will not change the content. If the content appears to be just text though, the core filter line break converter will be called on the content to break paragraphs appropriately.