tests: make filterpyflakes.py read target files relatively to cwd
Before this patch, 'filterpyflakes.py' reads target files relatively
to own location.
But this prevents third party tools from using it in own source tree,
because their files are placed separately from 'filterpyflakes.py'.
In fact, 'test-check-pyflakes.t', which is the only user of
'filterpyflakes.py', changes current working directory (cwd) to the
root of "test target" source tree before using it. Therefore,
composing the root of source tree in 'filterpyflakes.py' is redundant.
This patch makes 'filterpyflakes.py' read target files relatively to
cwd by invoking 'open()' without any path composition. This also
removes importing 'os' module, because there is no user of it after
this patch.
This is a one of preparation of
issue4677.
monoblue: remove unused elements and related css
Since
91b0ada2d94b and
c9b88695d894, when monoblue was introduced, the code
this patch removes was untouched. Presumably, there supposed to be nice
graphics in the screen corners, but there never were due to:
- the css being commented out
- ids of the elements and of the css selectors being different
- and the png files absent
The "corner" elements were unstyled and didn't affect the rest of the page, so
I think it's safe to remove all this.