Multiple start-symbols support

[flip111]

Would be great to have support for multiple start-symbols.

I guess it would not be difficult to add since the start rule is just found in the rules

Compiler/Llk/Parser.php

Line 173 in de036d5

$rule = $this->getRootRule();

Compiler/Llk/Parser.php

Lines 774 to 783 in de036d5

	public function getRootRule()
	{
	foreach ($this->_rules as $rule => $_) {
	if (!is_int($rule)) {
	break;
	}
	}
	return $rule;
	}