This fixes the change in python API introduced by
https://bugs.python.org/issue29463

Fixes #101.

If an f-string was ended with a newline character (more precisely, if
the last element of a JoinedStr node was just a newline character), its
round-trip source code representation would have an extra newline on
a wrong place, resulting in invalid syntax.

The bug affects only python>=3.6 (f-strings weren't supported before)

This commit fixes the aforementioned bug.

This commit also replaces pypy3.3-5.2-alpha1 tox/travis with pypy3.5.

The former PyPy version has a bug causing the tests to fail:

https://bitbucket.org/pypy/pypy/issues/2316/osget_terminal_size-is-missing-on-pypy3-hg

Fixes #89.

The domain astor.rtfd.org doesn't matched the certificate that is being served. so the documentation link resulted in a browser warning, rather than the docs.

Fixes #86

Fixes #87

Closes #82

Closes #37
Closes #36

* Fix Unicode issue #26 for Python 3 files.

* Refactor tests
 - Make it easier to test against other packages

* Split out optional tests and use assertXXX naming conventions

* Fix Python 3 test intrapackage import

* Fix Python 3 test intrapackage import

* Enhance code generator performance
- Algorithmic gains in pretty printer and string prettifier
- Diminishing gains from a few closures in code_gen
- One code-gen fix (and a test case) for None leaking into code-gen result list.
- rtrip gains via new fast comparison function
- PEP8 fixes

* Fix new deprecation warnings
  - Change to DeprecationWarning to reduce noise in other testers
  - Set stack level so warning appears with proper source line
  - Check for warning in test

* Explicitly verify warning content

  - Bonus:  works with all testrunners.

  -  We already pass these, but some other unparsers don't,
     so it's worth adding them to the regression.

Add support for __future__ unicode_literals

  -- This only affects a very few modules that did not roundtrip properly

Deprecate old API (issue #59)