modification.php with support for full OCmod-XML syntax

This update makes OCmod fully line-based, and with the same features, as in VQmod. It behaves like VQmod, except for using the OCmod-XML instead VQmod-XML syntax for the XML.

The search position includes: 'top','bottom', 'before', 'after', 'replace', 'ibefore', 'iafter'
Supported search attributes: trim, index, regex
Supported add attributes: trim,position, offset
Supported operation attributes: ignoreif, error