Improve performance of outputting text to screen
This change tries to improve the performance when you are outputting a
lot of text to the screen. Result with a 40M text file for me before was
6 seconds which is now down to about 2.5 seconds with this change. The changes are (mostly) just
container changes i.e., QVector/QList/ -> std::vector.
It can still be improved a lot more.
Edited by Waqar Ahmed