STY: Trailing whitespace clean up.

There're two trailing spaces in bipy/core/tests/test_distance (lines 435 and
448) that aren't removed because maybe they're there on purpose.
STY: More whitespace cleanup.
STY: New line at the end of file
STY: Replace multi-line string with trailing spaces with a list of lines.

See https://github.com/biocore/bipy/pull/85#issuecomment-34462868
TST: Stop ignoring warnings in pep8.

Somehow ignoring warnings makes it raise errors that shouldn't be
according to newer PEP8 versions. For instance, it'd complain when
using 2**4.
Merge pull request #88 from Jorge-C/whitespace

Whitespace