6.5.0

One new feature: the ability to supply a custom createElement function!

Otherwise, there are a few fixes around arbitrary HTML handling to avoid regex backtracking.

6b881ae adjust html regex to handle invalid HTML
d36798c workaround for parsing block html inside arbitrary html
ac20c7c Add createElement option (#152) ・Thank you @hugmanrique!
1e3b1d5 update the README ToC
d0f5fe2 fix heading level ・Thank you @pravdomil!
d5b4b12 minor changes in readme