Windows READMEs should be README.txt, native newlines

When creating a repository, or creating a new .svn work area, there
are README files which Windows users cannot easily double-click to read.

These files (and any other similar quick informational files) should
be named with a .txt file extension to facilitate easy reading via
GUIs, e.g., README.txt.  The Windows GUI cannot "associate" a default
action for files that have no extension.  It's okay with me if this is
only for files created by a Windows client, but it's not unheard of to
see "README.txt" files on Unixes too.

Also, and related, the client should create these README.txt files
with the appropriate native newline scheme, preferably regardless of
the current or default setting of the newline property.  Otherwise,
Windows readers get the unreadable single line in NOTEPAD.EXE.

Original issue reported by halley