EmphasisLikeParser

Should be used to parse emphasis-like elements with the same priority that should be aware of each other. Accepts a list of DelimiterParser that finds target delimiters runs and stores containing delimiters in the shared delimiters list. For each of those delimiters, this parser tries to find a matching closing delimiter. Matching information then is passed back to the DelimiterParser that should use it to create actual tree nodes.