tests/sitecustomize.py

mq/qqueue: add --purge option to delete a queue and its patch dir

qqueue --delete only deletes the reference to the queue, and leaves
the associated patch directory behind. There is no Mercurial-way of
getting rid of that patch directory afterward.

This patch adds the --purge option to qqueue, that deletes the queue
from the list, and also removes the associated patch dir. If the queue
was non-existant, but the patch dir was, it is removed nonetheless.

This is to avoid manual intervention in the .hg directory.

try:
    import coverage
    if hasattr(coverage, 'process_startup'):
        coverage.process_startup()
except ImportError:
    pass