Paragraph Block Edits

[snowfarthing]

The "MyCLI" command line client for MySQL and the browser console for JavaScript has the following features that make working with blocks of commands nicer to work with:

(1) blocks of lines representing one command are treated as one block to be edited,
(2) when using the up and down arrows to navigate lines, using up at the top of the block loads the previous block, using down at the bottom loads the second block,
(3) page up and page down load the previous and next blocks, respectively, and
(4) a block is submitted when "return" is pressed, and "ctrl-return" inserts a blank line in the block.

It would be really nice if this feature can be added to linedit!