(byte-compile-warning-types, byte-compile-warnings): New warning `noruntime'.

(byte-compile-warning-types, byte-compile-warnings): New warning `noruntime'.
(byte-compile-constants, byte-compile-variables): Fix docstring.
(byte-compile-initial-macro-environment): Use `byte-compile-eval' to
execute `eval-whenc-compile's body.
(byte-compile-unresolved-functions): Fix docstring.
(byte-compile-eval): New function.
(byte-compile-callargs-warn): Check if the function will be available
at runtime (via property `byte-compile-noruntime').
(byte-compile-print-syms): New function.
(byte-compile-warn-about-unresolved-functions): Also warn about
`noruntime' functions (and use `byte-compile-print-syms').
(byte-compile-file): Capitalize the message.