mux: support sending 405 Method Not Allowed
mux: fix minor linter issues
mux: change name of Options option and test it
mux: reduce code duplication in tests
mux: don't support host based matching
mux: be careful about complying with Go's license
mux: expand docs and add examples
mux: expand tests for route registration panics
mux: support OPTIONS requests by default
mux: panic if routes are unclean

Also remove some panic constants that weren't necessary
mux: support registration by HTTP method
mux: add route information to param metadata
mux: return param metadata
mux: factor out Param into own file
mux: factor out node type into own file
mux: remove already fixed TODO comment
mux: default not found headers to writing a 404
mux: move file pathmux.go to mux.go
all: prepare to publish
mux: cleanup docs and test empty path params
all: gitignore HTML code coverage reports