Making 'enter' easier

[kuanxu]

Currently, to ‘enter’ a line to begin debugging, one has to

1. run the file once first,
2. then add the @enter macro manually at the beginning of the line (Juno-based) or type in @enter (command-line-based),
3. If this is a line where value assignment is involved, one also has to remove the variable on the left-hand side as well as the equal sign.

Any of these can significantly drag the speed of the debugging work, let alone the combination, and it is very very error-prone as one has to modify the code unnecessarily. So it'll be great that debugging can start as simply as in Matlab - one can simply start debugging from the first line of the code or the line where the cursor is by just clicking one button when using Juno. In GDB, this can be done by run (if I recall correctly).

A ticket has also been filed here.