Don't use the abbreviation "win" to refer to Windows (Bug#10421).

Don't use the abbreviation "win" to refer to Windows (Bug#10421).

* lisp/org/ob-lilypond.el (ly-w32-ly-path): Rename from ly-win32-ly-path.
(ly-w32-pdf-path): Rename from ly-win32-pdf-path.
(ly-w32-midi-path): Rename from ly-win32-midi-path.
(ly-determine-ly-path, ly-determine-pdf-path, ly-determine-midi-path):
Check for "windows-nt", not "win32", in system-type.
* src/regex.c (MAX_BUF_SIZE): Remove some incorrect and
long-ago-commented-out code that talks about "WIN32".
* src/w32heap.h (OS_WINDOWS_95): Rename from OS_WIN95.
All uses changed.