Merge branch 'master' into 'master'

last PEP8 fixes (everything but E501 line too long and E123 close bracket indent)

These two commits fix all the rest of the PEP8 errors and warnings except for:

* E123 closing bracket does not match indentation of opening bracket's line
* E501 line too long (x > 79 characters)

Almost all of the fixed issues were these errors:

* E124 closing bracket does not match visual indentation
* E125 continuation line does not distinguish itself from next logical line
* E126 continuation line over-indented for hanging indent
* E127 continuation line over-indented for visual indent
* E128 continuation line under-indented for visual indent
* E226 missing whitespace around arithmetic operator

If you would like to make it run as part of the automated builds, it would just be a matter of adding this line to `jenkins-build`:

```
pep8 --ignore=E123,E501,W fdroid fdroidserver/*.py examples/*.py
```