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
```
* 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
fix pyflakes error and a bunch of PEP8 fixes
lots of little fixes here, the first commit fixes the minor error that `pyflakes` raised, then the rest are all PEP8 fixes, as reported by the `pep8` command line tool.
pyflakes gave this error based on the `paramiko = None` statement. I used
a different way to test whether paramiko was successfully imported that is
directly based on the relevant Exceptions.
Aside from the VM setup (which is now self-contained) the build process
only cares that it's handed a clean VM that it can access via ssh, given
a host/port/user/pubkey combination. There's no dependency outside the
getvm/releasevm functions on what kind of vm it is, what user the build
runs as, etc.
