'Create a dictionary with all metadata for the content.opf
file properly escaped.'

def content_metadata(self):

    metadata = {}
    metadata['title'] = self.esc(self.config.epub_title)
    metadata['author'] = self.esc(self.config.epub_author)
    metadata['uid'] = self.esc(self.config.epub_uid)
    metadata['lang'] = self.esc(self.config.epub_language)
    metadata['publisher'] = self.esc(self.config.epub_publisher)
    metadata['copyright'] = self.esc(self.config.epub_copyright)
    metadata['scheme'] = self.esc(self.config.epub_scheme)
    metadata['id'] = self.esc(self.config.epub_identifier)
    metadata['date'] = self.esc(datetime.utcnow().strftime('%Y-%m-%d'))
    metadata['manifest_items'] = []
    metadata['spines'] = []
    metadata['guides'] = []
    return metadata
