Some minor improvements to QUICKPROJECT:MAKE-PROJECT.

These are improvements to Quickproject that I do/use for every single project. It would be nice if they were included! The changes specifically are:

* Add an option to include the copyright, controlled by the variable
  `*INCLUDE-COPYRIGHT*`, which is exported.

* Move `:SERIAL T` next to the components list in the ASDF file.

* Add option to `MAKE-PROJECT` called `:INCLUDE-COPYRIGHT`, `NIL` by default.

* Change `README.txt` to `README`, as is more standard.