Minor changes and new `linkBtn` setting for `link` rows in TableView

I was reading the code to get better idea of how mobi-router works, these are some minor changes, some typos corrected, few functions documented and little extra documentation.

I had a use case where I needed `link` type rows to have buttons. I think this is quite usable as many times we need to perform some action when user clicks/touch the row and perform some different action when he clicks on the button in the row. I have added little documentation for this as well.

I also separated styles for TableView, moved them to a separate file in viewTypes dir.