Version 1.8.beta1, make MLF1 UTF-8-aware

After several attempts of a further development of the branch 1.x of My Little Forum, this is the first beta version of My Little Forum 1.8.

Features

• MLF1 now supports UTF-8 (database tables and columns, scripts, output), where it's reasonable also with 4.byte-chars (i.e. relevant for emojis)
• Change database engine for tables to InnoDB, what makes it possible to use transaction statements in the future
• Started the work on a template system mainly to separate the HTML sources from the overcrowded, confusing PHP-HTML-code mix

Changes

• Unified sending of e-mails with an external function
• Lines of cited text get not splitted anymore (again and again with every reply to a reply) but persist as one paragraph with only one quote char at the beginning of the paragraph
• Perform the check for a valid URL with the function filter_var what makes it necessary to run the forum with PHP 5.2 or newer
• remove most of the title-attributes from the HTML sources, because nowadays many users cannot access the attribute content with their devices
• Start to use HTML5 instead of XHTML1 in the separated and overworked templates
• Because of the move of icons and background images to the theme directory the old files in img can be deleted in case of an update from an older version

Fixes

• Check of e-mail-addresses now supports addresses with top level domains longer than 5 chars (example: 'museum' with 6 characters)
• Remove occurences of deprecated function each
• Inclusions of uploaded images get now an absolute URL in the RSS-feed, was broken until now because of it's relative URL