Make dukpy usable when installed.

[amcgregor]

Currently the tests pass because the package is installed via setup.py develop (indirectly, via pip install -e .) in travis.yml, which does not match a "user environment" where the package is installed normally via the Python Package Index, and bypasses a bug whereby the package_data directive in setup.py was incorrectly assuming recursive descent in the wildcard *.js declaration. The error exhibited as an inability for the installation utility to resolve the semver module, since the jsmodules tree was not installed.

This pull request corrects this issue, making the package usable when installed, not just when checked out and "installed in place". Additionally, it shortens some typing; instead of pip install -e . or python setup.py develop, now users on UN*X-like systems can just type ./setup.py develop. :)

[coveralls]

Coverage remained the same at 99.574% when pulling 81351b8 on illico:feature/installable into 409651b on amol-:master.

[amol-]

Thanks! That's something I missed when I moved all the js files inside subdirectories during last release :/

[amol-]

released as 0.0.4