BLAST+ 2.2.30 deliberately removed -word_size for RPS-BLAST

According to the BLAST developers (by email), the word size
is specified when the domain database is built, and so the
option should never should have been in rpsblast and rpstblastn.

TODO: Remove this from our rpsblast and rpstblastn wrappers.
Fix import not matching usage; PEP8

Spotted browsing landscape.io coding style report.
Remove unused import
Try to fix use of undefined variable in Bio.Geo; PEP8 whitespace

This probably needs more test coverage...
PhyloXMLIO: choose a default text encoding for XML output on Py2/3

Based on @peterjc's phyloxml_py3 branch.

Should resolve Issue #368 and Issue #334.
Merge remote-tracking branch 'upstream/master' into landscape