Feature Request: support .toSlice() and/or .toString() for an address

[mwherman2000]

...so that something like the following will work:

address foo = 0xe30b378de3b6a93cf1c26365f9280f5350bdcbfe;
string bar = "hello world! ".toSlice().concat(foo.toSlice());

Answer #5 in https://ethereum.stackexchange.com/questions/8346/convert-address-to-string/8347 is an implementation of address.toString()