wcsfilecmp: punctuation [\]^_` after A-Z.

This tweaks wcsfilecmp such that certain punctuation characters will
come after A-Z.

A big win with `set <TAB>` - the __prefixed fish junk now comes
after the stuff users should care about.

src/util.cpp

@@ -61,8 +61,8 @@ int wcsfilecmp(const wchar_t *a, const wchar_t *b) {
             if (retval || *a == 0 || *b == 0) break;
         }
 
-        wint_t al = towlower(*a);
-        wint_t bl = towlower(*b);
+        wint_t al = towupper(*a);
+        wint_t bl = towupper(*b);
         if (al < bl) {
             retval = -1;
             break;

tests/__fish_complete_directories.out

@@ -6,6 +6,8 @@ test/data/	Directory
 # __fish_complete_directories test/data/
 test/data/abc/	Directory
 test/data/abcd/	Directory
+test/data/fish-symlink/	Directory
+test/data/fish-symlink2/	Directory
 test/data/fish/	Directory
 test/data/xy/	Directory
 test/data/xyz/	Directory