Add support for custom site directory names

The path to the site directory is determined by the
HOTMELT_SITE_DIRECTORY constant. For standard setups this constant is
automatically defined in the default dispatch.php. To use a custom site
directory name, create a custom dispatch.php in your site directory and
define the HOTMELT_SITE_DIRECTORY constant before requiring the default
dispatch.php

Remember to update your .htaccess, so the rewrite rules point to your
custom dispatch.php.
Merge branch 'feature/custom-site-dir' into develop

The path to the site directory is determined by the
HOTMELT_SITE_DIRECTORY constant. For standard setups this constant is
automatically defined in the default dispatch.php. To use a custom site
directory name, create a custom dispatch.php in your site directory:

``` php
<?php
define('HOTMELT_SITE_DIRECTORY', dirname(__FILE__));
require_once(dirname(__FILE__).'/../HotMelt/dispatch.php');
```

Remember to update your .htaccess, so the rewrite rules point to your
custom dispatch.php.

closes #4
Remove text blocks feature

Remove HotMelt\Administration\TextBlockSiteController.
Remove HotMelt\TextBlockManager.
Remove HotMelt\TemplateView::textBlockManager().
Remove legacy PDO escape method

Remove HotMelt\PDO::escape(). The default PDO::quote() does the same
thing only better.
Remove redirection view feature

Remove HotMelt\RedirectionView. To redirect to another URL, just throw
a HotMelt\HTTPErrorException with a status code of 301 or 302 and
include a 'Location' header with the target URL.
Remove legacy code, fix legacy method spellings

- Rename HotMelt\Log::get_level() to getLevel().
- Rename HotMelt\PDO::MySQL() to mySQL().
- Rename HotMelt\PDO::Sqlite() to sqlite().
- Rename HotMelt\Request->HTTPAccept to httpAccept.
- Rename HotMelt\Request::HTTPServerRequest() to httpServerRequest().
- Rename HotMelt\Route::accepts_method() to acceptsMethod().
- Remove HotMelt\View->contentType.
Merge branch 'cleanup/legacy-1.1' into develop

Remove legacy code and fix legacy method spellings marked as deprecated
by version 1.1.0. Closes #5.
Add content type autodetection for .twig files
Merge branch 'bugfix/twig-html-content-type' into develop

Sets the autodetected content type for `.twig` files to `'text/html'`.

To override the default content type for a view, specify it explicitly:

**Site/routes.php:**

``` php
<?php
\HotMelt\Route::add('/^\/foo\.txt$/', 'MySite\\Site::foo', array('text/plain' ⇒ 'PlainText.twig'));
```

closes #6
Improve callable check when loading a route's action

When loading a route's action lazily, test for callability more
sensibly. Rely on is_callable() for this and stop sniffing the string
representations for '::'.

Allow both null and false to identify the default action.

fixes #1
Make HotMelt\Action::defaultAction() static

HotMelt\Action::defaultAction() should have been implemented as static
all along.

fixes #7
Merge branch 'bugfix/action-callables' into develop

Make HotMelt\Action::defaultAction() static (fixes #7).

Improve callable check when loading a route's action (fixes #1).

Allow both null and false to identify the default action.
Merge branch 'develop'

- Add support for custom site directory names (closes #4).
- Remove legacy code and fix legacy method spellings marked as
  deprecated by version 1.1.0 (closes #5).
- Sets the autodetected content type for .twig files to
  'text/html' (fixes #6).
- Improve callable check when loading a route's action (fixes #1).
- Make HotMelt\Action::defaultAction() static (fixes #7).