File forgotten in previous commit

Merge commit 'origin'

Created the LogFilteredData class and associated unit test.

Added a basic implementation of the bottom window. Only the graphical
part is done, no functionnality is implemented.

Added a unit test suite for LogData

Added a working vertical scrollbar

Added a proper logging system.

Now display the real files (but without scrolling)!

Replaced the QTextEdit as a main widget by a QSplitter, with a QLabel in place of the search window.

First nearly functional version with a readonly QTextEdit widget as main widget

Initial import