request_handler: fix handling of file:

It should skip file: and file://, not only file:

Fix #208.
docs/news: added release notes for 0.4.10
setup: bump to 0.4.10
zope.testbrowser supports `is_text_present`
Fix try/except of zope.testbrowser's `is_text_present` and enable tests to that feature. Refs #210
make deps: refactored to use pip.
make doc_deps: refactored to use pip.
make test: executing report only if all tests are ok.
Merge branch 'issue-206' of github.com:cobrateam/splinter into issue-206