refactor(tests/helper.py)

This change breaks out the common functionality from
the unit tests into a testsuite package that allows
users of Falcon to unit test their API's using
a similar technique.
Merge remote-tracking branch 'upstream/master'

Conflicts:
	tests/test_hello.py
	tests/test_wsgi_errors.py
refactor($testing): testsuite -> testing

This commit changes the testing framework namespace
from testsuite to testing and fixes two comment
style violations.
Merge remote-tracking branch 'upstream/master' into testing_refactor

Conflicts:
	tests/test_headers.py
fix(@style): Fixes comment violations.
fix(testing): Make _simulate_request work w/ bin

TestSuite._simulate_request inferred that all body input
was binary. This change allows detection of unicode
data types and only attempts the conversion to utf-8
if necessary.
Merge remote-tracking branch 'upstream/master' into testing_refactor

Conflicts:
	tests/test_headers.py
style: Comments and more idiomatic type checks

Updates comments with default values and uses
the idiomatic (and slightly faster) isinstance
instead of type comparison.

Also replaces
Merge remote-tracking branch 'upstream/master' into testing_refactor

Conflicts:
	tests/test_http_method_routing.py
Merge pull request #67 from painterjd/testing_refactor

feat: Add testing helps and mocks for Falcon-based apps.

Closes #5