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/alg/arraylist2.internal.h

@@ -0,0 +1,37 @@
+#ifndef COSMOPOLITAN_LIBC_ALG_ARRAYLIST2_H_
+#define COSMOPOLITAN_LIBC_ALG_ARRAYLIST2_H_
+#include "libc/mem/mem.h"
+#include "libc/str/str.h"
+#if !(__ASSEMBLER__ + __LINKER__ + 0)
+COSMOPOLITAN_C_START_
+
+/* TODO(jart): Fully develop these better macros. */
+
+#define APPEND(LIST_P, LIST_I, LIST_N, ITEM) \
+  CONCAT(LIST_P, LIST_I, LIST_N, ITEM, 1)
+
+#define CONCAT(LIST_P, LIST_I, LIST_N, ITEM, COUNT)                     \
+  ({                                                                    \
+    autotype(LIST_P) ListP = (LIST_P);                                  \
+    autotype(LIST_I) ListI = (LIST_I);                                  \
+    autotype(LIST_N) ListN = (LIST_N);                                  \
+    typeof(&(*ListP)[0]) Item = (ITEM);                                 \
+    size_t SizE = sizeof(*Item);                                        \
+    size_t Count = (COUNT);                                             \
+    ssize_t Entry = -1;                                                 \
+    /* NOTE: We use `<` to guarantee one additional slot */             \
+    /*       grow() will memset(0) extended memory, thus */             \
+    /*       you get a nul-terminator for free sometimes */             \
+    /*       the exception is if you list.i=0 and re-use */             \
+    /*       so you need concat(...); list.p[list.i++]=0 */             \
+    if (*ListI + Count < *ListN || __grow(ListP, ListN, SizE, Count)) { \
+      memcpy(&(*ListP)[*ListI], Item, (SizE) * (Count));                \
+      Entry = *ListI;                                                   \
+      *ListI += Count; /* happens after copy in case signal */          \
+    }                                                                   \
+    Entry;                                                              \
+  })
+
+COSMOPOLITAN_C_END_
+#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
+#endif /* COSMOPOLITAN_LIBC_ALG_ARRAYLIST2_H_ */