Import C++ Standard Template Library

You can now use the hardest fastest and most dangerous language there is
with Cosmopolitan. So far about 75% of LLVM libcxx has been added. A few
breaking changes needed to be made to help this go smoothly.

- Rename nothrow to dontthrow
- Rename nodiscard to dontdiscard
- Add some libm functions, e.g. lgamma, nan, etc.
- Change intmax_t from int128 to int64 like everything else
- Introduce %jjd formatting directive for int128_t
- Introduce strtoi128(), strtou128(), etc.
- Rename bsrmax() to bsr128()

Some of the templates that should be working currently are std::vector,
std::string, std::map, std::set, std::deque, etc.

examples/examples.mk

@@ -51,7 +51,6 @@ EXAMPLES_DIRECTDEPS =						\
 	LIBC_NT_USER32						\
 	LIBC_NT_WS2_32						\
 	LIBC_NT_ADVAPI32					\
-	LIBC_OHMYPLUS						\
 	LIBC_RAND						\
 	LIBC_RUNTIME						\
 	LIBC_SOCK						\
@@ -73,6 +72,7 @@ EXAMPLES_DIRECTDEPS =						\
 	THIRD_PARTY_DLMALLOC					\
 	THIRD_PARTY_GDTOA					\
 	THIRD_PARTY_GETOPT					\
+	THIRD_PARTY_LIBCXX					\
 	THIRD_PARTY_LINENOISE					\
 	THIRD_PARTY_LUA						\
 	THIRD_PARTY_MBEDTLS					\