Rewrite memory manager

Actually Portable Executable now supports Android. Cosmo's old mmap code
required a 47 bit address space. The new implementation is very agnostic
and supports both smaller address spaces (e.g. embedded) and even modern
56-bit PML5T paging for x86 which finally came true on Zen4 Threadripper

Cosmopolitan no longer requires UNIX systems to observe the Windows 64kb
granularity; i.e. sysconf(_SC_PAGE_SIZE) will now report the host native
page size. This fixes a longstanding POSIX conformance issue, concerning
file mappings that overlap the end of file. Other aspects of conformance
have been improved too, such as the subtleties of address assignment and
and the various subtleties surrounding MAP_FIXED and MAP_FIXED_NOREPLACE

On Windows, mappings larger than 100 megabytes won't be broken down into
thousands of independent 64kb mappings. Support for MAP_STACK is removed
by this change; please use NewCosmoStack() instead.

Stack overflow avoidance is now being implemented using the POSIX thread
APIs. Please use GetStackBottom() and GetStackAddr(), instead of the old
error-prone GetStackAddr() and HaveStackMemory() APIs which are removed.

third_party/dlmalloc/README.cosmo

@@ -9,9 +9,9 @@ LICENSE
 
 LOCAL CHANGES
 
-  - Use thread-local freelist from cosmo tib
+  - Define dlmalloc_requires_more_vespene_gas()
+  - Make dlmalloc scalable using sched_getcpu()
   - Use faster two power roundup for memalign()
-  - Poison maps to integrate with Address Sanitizer
-  - Introduce __oom_hook() by using _mapanon() vs. mmap()
-  - Wrap locks with __threaded check to improve perf lots
-  - Use assembly init rather than ensure_initialization()
+  - Implemented the locking functions dlmalloc wants
+  - Use assembly _init() rather than ensure_initialization()
+  - Rather than calling mmap() 96 times from _start() just use .bss