travis: build docs with warnings as errors
docs: add _static dir just in case
flask: drop flaskext_compat

If we bump up our minimum requirements we can drop this compat layer.
psyco: drop it, it is unsupported

While it might work on Python 2.6, most people won't be running on that
anyway and we won't be for amagama.locamotion.org

So remove it so we don't need to maintain it.
travis: test for PEP8 conformance
PEP8: E111 indentation is not a multiple of four
PEP8: W391 blank line at end of file
PEP8: E261 at least two spaces before inline comment
PEP8: E502 the backslash is redundant between brackets
PEP8: E231 missing whitespace after ','
PEP8: E251 unexpected spaces around keyword / parameter equals
PEP8: E302 expected 2 blank lines, found 1