Started revising and testing ee_caret, which lead to some rethinking of ee_buffer and its specification. A number of tests are currently failing.
Changed design in ee_buffer so that empty line list is not allowed and empty buffer is represented by a single empty line.
Changed design in ee_caret so that it allows the caret to be outside of the buffer domain, and will be adjusted to a valid buffer coord in call to caret_to_buffer_coords().
Made dbg_print macro always be active and improved output somewhat.