Set the request context on caught HTTP_Exceptions

When HTTP_Exceptions are caught inside of the Internal Request Client,
the current request will be set inside of the Exception using the
HTTP_Exception::request() method.

This fixes #4635
doc: use "303 See Other" redirects after POST

Per RFC 2616 (HTTP 1.1), the HTTP response status code "303 See Other"
is the correct way to redirect a client after an HTTP POST. Adjust the
documentation to use a 303 redirect instead of 302.
Fixes #4662: Response returning the wrong protocol
Fixes #4657: Reset the globals after running the tests
Fixes #4718: Duplicate unnecessary line that is not used anymore
Merge pull request #362 from rjd22/3.3/bugfix/unnecessary_variable_in_exception

Fixes #4718: Duplicate unnecessary line that is not used anymore
Merge pull request #361 from rjd22/3.3/bugfix/globals_reset_in_test

Fixes #4657: Reset the globals after running the tests
Merge pull request #358 from rjd22/3.3/bugfix/wrong_http_headers

Fixes #4662: Response returning the wrong protocol
Merge pull request #316 from EvanPurkhiser/fixup/4635

Set the request context on caught HTTP_Exceptions
refs #4635
Fixes #4637: Replace iconv with mb_convert_encoding for beter support in PHP 5.4.3+
Merge pull request #363 from rjd22/3.3/bugfix/replace_iconv_with_mb_convert_encoding

Fixes #4637: Replace iconv with mb_convert_encoding for beter support in...
Fixes #4658: Fixed the error in guide
Fixes #4744: Arr::path now also accepts arrays
Added Test for Using arrays in set path
Merge pull request #365 from rjd22/3.3/feature/arr_set_path_should_accept_arrays

Fixes #4744: Arr::set_path now also accepts arrays
Merge pull request #364 from rjd22/3.3/bugfix/mistake_in_mvc_guide

Fixes #4658: Fixed the error in guide
Forgot to fix the quote
Merge pull request #367 from rjd22/3.3/bugfix/mistake_in_mvc_guide

Forgot to fix the quote for #4658
Fixing returns in PHPdoc

My IntelliJ (IDE) complains in the method handler() because the PHPdoc for Kohana_Exception::_handler() told it that a boolean was returned. The "boolean" was then used as an Response object. Since a Response was the actual returned value, I fixed the PHPdoc.
Merge pull request #373 from HNygard/patch-1

Fixing returns in PHPdoc

Refs #4762