Convert docs to markdown

[mvorisek]

regexes used for most of the conversions:

$d = preg_replace("~\n*===+\n(.+?)\n===+\n*~", "\n\n# $1\n\n", $d);
$d = preg_replace("~\n*(.+?)\n===+\n*~", "\n\n## $1\n\n", $d);
$d = preg_replace("~\n*(.+?)\n---+\n*~", "\n\n### $1\n\n", $d);
$d = ltrim($d);

$d = preg_replace_callback("~(?<=\n|^)(?:    .*)(?:\n(?:    .*|))*(?<!\n)~", function ($matches) { return "```\n" . preg_replace("~(?<=\n|^)    ~", 'ůůůů', $matches[0]) . "\n```"; }, $d);
$d = preg_replace("~ůůůů~", "", $d);
$d = preg_replace_callback("~(?<=\n|^)(?:\.\. ?)code-block:: *+(.*)\n*((\n(?:    .*|))*)(?<!\n)~", function ($matches) { return "```" . $matches[1] . preg_replace("~(?<=\n|^)    ~", 'ůůůů', $matches[2]) . "\n```"; }, $d);
$d = preg_replace("~ůůůů~", "", $d);
$d = preg_replace_callback("~(?<=\n|^)(?:\.\. ?)((?!\n|:(?=:)|(?<=:):).+):: *+(.*)\n*((\n(?:   *.*|))*)(?<!\n)~", function ($matches) { return ":::{" .  $matches[1] . "}" . (trim($matches[2]) !== '' ? ' ' . trim($matches[2]) : '') . preg_replace("~(?<=\n|^)   *~", 'ůůůů', $matches[3]) . "\n:::"; }, $d);
$d = preg_replace("~ůůůů~", "", $d);
$d = preg_replace("~::(?=\n+```\n)~", ":", $d);
$d = preg_replace("~(?<!`)``(?!`)~", "`", $d);
$d = preg_replace("~`(.+?) ?<(https?:.*?)>`_~", "[$1]($2)", $d);
$d = preg_replace("~(?<=\n) +(?=(?:-|\d+\.|\*))~", "", $d);
$d = preg_replace("~(?<=\n)> ?~", "", $d);
$d = preg_replace("~:(php:[^: `\n]+):`([^`]+)`~", "{\$1}`$2`", $d);
$d = preg_replace("~:(ref):`([^`]+)`~", "{\$1}`$2`", $d);
$d = preg_replace("~:(.+?):`(.+?)`~", "{\$1}`$2`", $d);
// https://github.com/markstory/sphinxcontrib-phpdomain/issues/55 $d = preg_replace("~(?<=\n)(:\w+[ :].+\n)+~", "```{eval-rst}\n$0```\n", $d);
$d = preg_replace("~(?<=\n|^)\.\. ?_([\w\-]+):(?=\n|$)~", "($1)=", $d);