General TODO:
* For the GUI, we'll start with making a new QObject class, for
  this.
* Import all the functions under the QObject class (tiring work)
* Get the barebones GUI working
* Move the existing functions in MainWindow, entirely to the new
  QObject class
* Select a name for the QObject class
* Guess I just did: FunctionClass :P
Start with the add() function!
Some UI changes, add Documentation (WIP)
Add a "clear" button
code: move add, subt, mult, divide functions to FunctionClass
ui: always set focus on line_input (saves time ;) )
move fibonnacci_print, nth_root, power_number to FunctionClass
move odd_nos_print, even_nos_print
move dec2bin, dec2oct, dec2hex, bin2dec, oct2dec to FunctionClass
move check_prime, factor_print, max_number, average to FunctionClass
move all temperature functions to FunctionClass
move quicksqrt and invsqr to FunctionClass
move some more functions to FunctionClass
Remove cglobal from usable code
//todo: cleanup leftover cglobal code
update todo
//working on cleanup.
cleanup code:
    use spaces instead of tabs
    cleanup cglobal code
    add/update general copyright in all files
ui: add a quit button
    rework ui a little
ui: Add some custom fonts
ui: setWindowTitle
fixup a warning
ui: set min/max size to 640x480. this prevents phucked up dimens.
ui: set cursor to pointing hand on button hover
ui: set clear button visibility, only upon existence of text