Get Cosmopolitan into releasable state

A new rollup tool now exists for flattening out the headers in a way
that works better for our purposes than cpp. A lot of the API clutter
has been removed. APIs that aren't a sure thing in terms of general
recommendation are now marked internal.

There's now a smoke test for the amalgamation archive and gigantic
header file. So we can now guarantee you can use this project on the
easiest difficulty setting without the gigantic repository.

A website is being created, which is currently a work in progress:
https://justine.storage.googleapis.com/cosmopolitan/index.html

libc/str/oldutf16.internal.h

@@ -0,0 +1,47 @@
+#ifndef COSMOPOLITAN_LIBC_STR_OLDUTF16_H_
+#define COSMOPOLITAN_LIBC_STR_OLDUTF16_H_
+#if !(__ASSEMBLER__ + __LINKER__ + 0)
+COSMOPOLITAN_C_START_
+
+unsigned getutf16(const char16_t *, wint_t *);
+int pututf16(char16_t *, size_t, wint_t, bool);
+
+#define pututf16(BUF, SIZE, CH, AWESOME) __pututf16(BUF, SIZE, CH, AWESOME)
+#define getutf16(BUF, CHPTR)             __getutf16(BUF, CHPTR)
+
+forceinline int __pututf16(char16_t *s, size_t size, wint_t wc,
+                           bool32 awesome) {
+  if (size >= 1 && (0x00 <= wc && wc <= 0xD7FF)) {
+    if (wc >= 32 || !awesome) {
+      s[0] = (char16_t)wc;
+      return 1;
+    } else if (size >= 2) {
+      s[0] = 0xd800;
+      s[1] = 0xdc00 | (char16_t)wc;
+      return 2;
+    }
+  }
+  int ax;
+  asm("call\tpututf16"
+      : "=a"(ax), "=m"(*(char(*)[size])s)
+      : "D"(s), "S"(size), "d"(wc)
+      : "cc");
+  return ax;
+}
+
+forceinline unsigned __getutf16(const char16_t *s, wint_t *wc) {
+  if ((0x00 <= s[0] && s[0] <= 0xD7FF)) {
+    *wc = s[0];
+    return 1;
+  }
+  unsigned ax;
+  asm("call\tgetutf16"
+      : "=a"(ax), "=m"(*wc)
+      : "D"(s), "S"(wc), "m"(*s), "m"(*(char(*)[4])s)
+      : "cc");
+  return ax;
+}
+
+COSMOPOLITAN_C_END_
+#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
+#endif /* COSMOPOLITAN_LIBC_STR_OLDUTF16_H_ */