autodetect line endings

When GLib code is checked out with Windows line endings (happens on Windows), embedded that line endings into generated string literal. And
then they translated to double newlines in glib-compile-resources output.

clang-cl failed to compile such files because of empty lines in the middle of
multiline macros:

    #define G_MSVC_CTOR(_func,_sym_prefix) \

      static void _func(void); \

To fix the issue, enable 'universal newlines' mode when reading the input in - translate both '\n' and '\r\n' to '\n'.

Fixes GNOME/glib#2340
10 jobs for fix-data-to-c-line-endings in 23 minutes and 29 seconds (queued for 1 second)