add work for the new extension system (bugs #1491, #1500, #1555)
treebd2b0e7d0bb25659b5c626c7ce5122b21c1d7041
drwxr-xr-x - .tx
-rw-r--r-- 35147 COPYING
-rw-r--r-- 143 MANIFEST.in
-rw-r--r-- 5255 README
drwxr-xr-x - bin
drwxr-xr-x - data
drwxr-xr-x - draft
drwxr-xr-x - examples
-rw-r--r-- 5303 makefile
-rw-r--r-- 4801 setup.py
drwxr-xr-x - src
drwxr-xr-x - tools