[WIP] Release v1.0

This is a work-in-progress pull request for the next major release v1.0 which is going to be released in December.

### Changes of specification (backward-incompatible)

- [x] Change the data type of HTTP headers in ENV (#80)
- [x] Change the data structure of parameters in Clack.Request (#81)

### Replacing by other libraries

- [x] Replace `clack.util.hunchentoot:mime-type` by [Trivial-Mimes](https://github.com/Shinmera/trivial-mimes)
- [x] Replace `clack.util.hunchentoot:parse-rfc2388-form-data` by [HTTP-Body](https://github.com/fukamachi/http-body).
- [x] Replace `clack.util.hunchentoot:url-decode` by [QURI](https://github.com/fukamachi/quri).

### Deleting unnecessary/obsolete packages

- [x] Delete Clack.Handler.Apache2 because mod_lisp2 is abandoned and it's deprecated now.
- [x] Delete clack.middleware.json because HTTP-Body treats also application/json.
- [x] Delete clack.util.localtime. Use [local-time](http://common-lisp.net/project/local-time/manual.html) directly.
- [x] Delete clack.util.route and clack.app.route because they are deprecated. Use [My Way](https://github.com/fukamachi/myway) instead.
- [x] Delete clack.util.stream because it's not used anymore.
- [x] Delete `clack.util:make-tmp-file-name` because it's not used anymore.

### Other improvements

- [x] Don't require multithread feature in handlers.
- [x] Replace do-urlencode by more efficient implementation ([QURI](https://github.com/fukamachi/quri)).