[Patch] replace hardcoded icon size with correct system value in applet handle

[Loïc Marteau]

http://reviewboard.vidsolbach.de/r/76/

m_iconSize = IconSize(KIconLoader::Small);

I have choose this method to get the correct system size.
KIconLoader::Small is 16 pix by default (as we have before), so if the
user has changed the default setting for the small icons m_iconSize
get the correct system dedicated value choosed by the user.

Cheers