Add a minimal .gitignore.

Ignore PYC files, as well as build artifacts.
Fix Python 3 compatibility.

* iteritems() is Python 2 only
* In Python 3, the except handler's "name" is a string, not a node
Fix importer fixup() of module and from-symbol name.

This makes the import_test pass again.
The index_test have to be adapted to check for the right result.
Fix swallowing up trailing comments in an import block.

Fixes the remaining failing test test_imports_dont_delete_trailing_comments.
Add travis integration.
Merge pull request #2 from birkenfeld/travis

Test travis