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.