fix ci builds (PPSD and others)

[d-chambers]

What does this PR do?

This PR attempts to get the travis CI working again.

Why was it initiated? Any relevant Issues?

Travis is failing

PR Checklist

• Correct base branch selected? master for new features, maintenance_... for bug fixes
• This PR is not directly related to an existing issue (which has no PR yet).
• If the PR is making changes to documentation, docs pages can be built automatically.
  Just remove the space in the following string after the + sign: "+ DOCS"
• If any network modules should be tested for the PR, add them as a comma separated list
  (e.g. clients.fdsn,clients.arclink) after the colon in the following magic string: "+TESTS:"
  (you can also add "ALL" to just simply run all tests across all modules)
• All tests still pass.
• Any new features or fixed regressions are be covered via new tests.
• Any new or changed features have are fully documented.
• Significant changes have been added to CHANGELOG.txt .
• First time contributors have added your name to CONTRIBUTORS.txt .

[QuLogic]

Well, it's definitely looking better... We need to decide on something for the pickling thing to fix the last few bits (except the Python 2.7 build).

[d-chambers]

It looks like py 2.7 the min dep. version is missing gfortran still, perhaps related to the issue you opened? I will try explicitly installing it on the min dep build.

[d-chambers]

Travis 2.7 build is still failing, any ideas on that one?

[QuLogic]

Hmm, I'm confused. Both pip freeze and conda list say NumPy is installed, so it should be... It must be failing to load some shared library dependency or something, but the message is not too clear. Try running a simple script that just import numpy and see what the real error is?

We should get out 1.2.0 and drop Python 2.7 support ASAP.

[megies]

Thanks! Huge improvement, I'm merging this now, we can check out 2.7 later, I guess..