Deprecate java.io.File or at least some methods

[Remi Forax]

Hi all,
restarting discussion about JDK-8181098,
java.io.File has several severe issues so we should alert users to migrate to use java.nio.file.[Path|Files] ASAP using the deprecation mechanism (obviously not for removal).

The usual gotchas
- File used string name which may do not map correctly with the underlying file system charset.
- methods that are developer hostile 
  - methods that performs an action on the file system file returns a false if there is an issue instead of an IOException
  - methods that list files return null instead of an IOException if there is an issue.
- reading/writing into a file (using File[InputStream|OutputStream|Reader|Writer]) doesn't default to UTF8.

I see two ways of deprecation, one is to deprecate the whole class, it has the advantage of making the things clear, the other is to deprecate the constructors and all methods that acts on the file of the file system. The later option allows library to still have methods that takes a java.io.File as parameter if their implementation use toPath() to perform the operations.

regards,
Rémi