STYLE: remove shebang from LogFunctions

- file is to be sourced, non-executable.

- remove stray .keep file from tutorial case

bin/tools/LogFunctions

-#!/bin/sh
-#------------------------------------------------------------------------------
+#---------------------------------*- sh -*-------------------------------------
 # =========                 |
 # \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
 #  \\    /   O peration     |