Add travis ci

[pierreinglebert]

Add travis ci for continuous integration.

[lovell]

Thank you for adding this.

There used to be a Travis CI job for this module. I (temporarily) removed it when sharp needed features of libvips added after v7.28, which is currently the highest version supported via package for Ubuntu 12.04 LTS as used by Travis CI.

To return the Travis CI job to its former glory, a before_install directive with shell commands to install dependencies and build libvips from source are required. I'm happy to add this if you'd like, or feel free to update this PR.

[pierreinglebert]

https://travis-ci.org/pierreinglebert/sharp/jobs/22136822

Not easy to test :D
it currently supports tiff/jpeg/png and libmagick but not webp

I also get an error when launching tests

libvips.so.37: cannot open shared object file: No such file or directory

If you have an idea of what is going on, that would be awesome ^^

[lovell]

No worries, I'll take a look. I do remember this being non-trivial at the time, hence the temporary removal.

[lovell]

The travis branch contains my (rebased) commits to get this working.

All tests pass on Node.js stable v0.10.25

https://travis-ci.org/lovell/sharp/builds/22226802

The module fails to build with Node.js unstable v0.11.11 but I can see lots of activity preparing for a new release of nan including support for Node.js v0.11.13, which should solve the compilation errors.

[pierreinglebert]

Nice !
There are also issues with natives modules building in the 2 last releases.