disco: don't depend on :python.

Use the system Python instead.
disco: add test.
bottle_version: parse disco bottle versions.
dtrx: don't depend on :python.

Use the system Python instead.
duplicity: don't depend on :python.

Use the system Python instead.
euca2ools: don't depend on :python.

Use the system Python instead.
googlecl: don't depend on :python.

Use the system Python instead.
hg-flow: don't depend on :python.

Use the system Python instead.
ice: don't depend on :python.

Use the system Python instead.
ice: add test.
ice: fix audit.
mackup: don't depend on :python.

Use the system Python instead.
mercurial: don't depend on :python.

Use the system Python instead.
mercurial: fix test.
mimms: don't depend on :python.

Use the system Python instead.
mitmproxy: don't depend on :python.

Use the system Python instead.
mkvtomp4: don't depend on :python.

Use the system Python instead.
namebench: don't depend on :python.

Use the system Python instead.
namebench: add test.
pebble-sdk: don't depend on :python.

Use the system Python instead.