Hello,

The attached patch adds for at expanding the sexp before point using 
`macroexpand-all` instead of `macroexpand`.  This is useful when the 
expansion contains macros that could be further expanded. I have been 
using it for several years in my own config.

I have named these commands 'pp-macroexpand-all-last-sexp ' and 
'pp-macroexpand-all-expression '. They could also be called 
'pp-macroexpand-last-sexp-all' and 'pp-macroexpand-expression-all'. 
Please let me know if you would prefer different names.

Thank you.