Fixed gitignore to reflect changes in moc/ui file naming.

Finally, the simple fix for the qtgui issues; also, changed the naming scheme output from _moc to .moc files because I think this looks cleaner.

Removing Waterfall3DPlot. The qwt_plot3d is too much of a hassle to deal with and the plotting is not that stable even when it does work. This does not change the API.

Update config.guess and config.sub in gr-howoto-write-a-block too

Update script to pull config.* from git repo