add interpolateBoxFilter

linear interpolation for results of BoxFilter, so that we don't destroy
solvers completely...
use any box size with any chunk for big cutout
bugfix --- correct loops in big cutout
remove debug message
bugfix -- integration times are now as intended

current version gives option to go over the largest time available in
the database, be careful.
move C file in its own folder
move files and create minimal setup.py
add channel grid data files to distribution
installation works

note:
1. I included the "shlib" module which comes from
http://www.ctcms.nist.gov/oof/oof2/index.html.
They say it's not copyrighted, so I guess it's ok.
2. I'm not sure how we can control the place where the shared object is
going to be placed, although I don't think that's going to be a problem
in the long run.
comment out install_requires

as far as I know that's typical to setuptools, so it's not gonna work
for us anyway.
also, change some "from bla import bla" to "import bla" etc, because I
wanted to check if it was possible to fool Python by deleting modules.
Apparently not.
use only setuptools

apparently, we can do shared libraries just with distutils (or
setuptools). so I ditched the shlib stuff...
reorganize commands in setup.py
read in __version__ at import time

thank you stackoverflow. again.
put libJHTDB in its own file
fix and put all tests in one file
bugfix --- import all required objects in test
ignore installation stuff
use default auth_token in test_misc
read user's auth_token from file

TODO: put file in some reasonable location, rather than straight in the
home folder.
Merge branch 'feature-installation' into develop