Merge pull request #76 from SimonPersson/master

Let response.render() take any encodable type.
fix(mustache): temporally switch to fork
response: Cleaner imports + less lock contention for rendering.
static_files: Simplify + less allocation.
router,middleware,query+misc: Reduce allocations per request.
urlencoded: Use Groupable.
urlencoded: Simplify tests.
router: Fix warnings.
query_string: Slightly more robust parsing.
query_string: Refactor tests.
query_string: Style.
feat(response): implement chaining API for content_type

Fixes #45
Fixes #41
docs(response): fixup doc for content_type
feat(response): implement chaining status_code API
chore(response): remove outdated comment
chore(response): moving chaining APIs to the top
docs(response): document send_file method
feat(travis): add integration
chore(readme): show travis badge
fix(Readme): fix travis badge