Added "lovedebug.lua"

Added "lovedebug.lua" from
https://love2d.org/forums/viewtopic.php?f=5&t=76742

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Complete list of features:
A scrollable list of the output.
Some errors are reedirected to the console instead of crashing löve.
Only prints the same error once, useful for errors in love.update, can
be toggled.
Semi-transparent console overlay, the console's color can be changed in
_DebugSettings.OverlayColor
CTRL/Shift + F8 toggle of the console
Text input for executing lua snippets right in your console
Graphic feedback telling about unseen lines ("..." on the bottom right)
Variable proposal and autocomplition (select a proposal by using the
arrow keys and press tab to autocomplete).
Fast jumping to the bottom of the console by pressing lCtrl+Middle mouse
button or by providing a code to the console.
Use the home and the end keys to jump to the end or to beginning of the
line.
Browse code history by using the arrow keys while pressing the Shift
key.
LiveCoding, you can reload your code by pressing F5 while at the console
or by setting _DebugSettings.LiveAuto to true and you can reload more
than one file, see _DebugSettings.Settings().
Type 'clear' and press enter to clear the console.
Type Ctrl+C/V to copy or to past text into the console input.