joiner: handle file moved events as well

When a file is moved from one location to the target location, the
source location may not match what is required for the target
location (for example, when the target location is a file). We handle
this. This fixes a regression in 5c73ce.
Merge pull request #28 from vincentbernat/fix/detect-file-move

joiner: handle file moved events as well
joiner: on some version of watchdog, the destination path is `dest_path`, not `dst_path`
php: fix dumping of arrays with integers

Python `join()` function only handles strings. We need to ensure that
we only provide strings.
php: handle booleans

Booleans were not handled when serializing to PHP.
Merge pull request #29 from vincentbernat/fix/detect-file-move

joiner: on some version of watchdog, the destination path is `dest_path`...
Merge pull request #30 from vincentbernat/fix/php-arrays

php: fix dumping of arrays with integers
Merge pull request #31 from vincentbernat/fix/php-booleans

Fix/php booleans
tests: add support for tox

We also enable to run unittests from setup.py. This requires some
changes, like adding the needed dependencies but also we have to be
able to run setup.py with dependencies missing. We also need to ship
files needed by setup.py.
tests: make test work with Python 2.6 as well
tests: use Travis-CI for tests
Merge pull request #33 from vincentbernat/feature/tox

Use tox to run unittests