Optional support of unexpected elements

[cbrow111]

Because encode/xml discards anything that isn't handled explicitly, unexpected changes would result in lost data. Golang provides the ,any and ,any,attr tags to handle elements that aren't explicitly mapped. Adding an argument to the binary like -support-unexpected-elements could be used to insert an array of interface{} on each generated struct with the any struct tag. This could allow the caller to check it at runtime and used to notify support of the need to scan files containing unexpected elements and regenerate structs.

[twpayne]

This is a great observation and would be a really nice improvement to this project. Would you like to work on this?

[cbrow111]

I'd be happy to.