fix #59 #57 #43 . use html5lib by default unless user-specified a html parser. If neither exist then default to BS4 to decide. use final redirect URL while requesting from server.
fix #59 #57 #43 . use html5lib by default unless user-specified a html parser. If neither exist then default to BS4 to decide. use final redirect URL while requesting from server.

tommorris/mf2py,tommorris/mf2py