esp8266: Enable more features in mpconfigport.h.

This is to get the test suite running and passing.

esp8266/mpconfigport.h

@@ -16,6 +16,7 @@
 #define MICROPY_HELPER_LEXER_UNIX   (0)
 #define MICROPY_ENABLE_SOURCE_LINE  (1)
 #define MICROPY_MODULE_WEAK_LINKS   (1)
+#define MICROPY_CAN_OVERRIDE_BUILTINS (1)
 #define MICROPY_PY_BUILTINS_COMPLEX (0)
 #define MICROPY_PY_BUILTINS_STR_UNICODE (1)
 #define MICROPY_PY_BUILTINS_BYTEARRAY (1)
@@ -27,12 +28,14 @@
 #define MICROPY_PY___FILE__         (0)
 #define MICROPY_PY_GC               (1)
 #define MICROPY_PY_ARRAY            (1)
+#define MICROPY_PY_ARRAY_SLICE_ASSIGN (1)
 #define MICROPY_PY_COLLECTIONS      (1)
 #define MICROPY_PY_MATH             (1)
 #define MICROPY_PY_CMATH            (0)
 #define MICROPY_PY_IO               (1)
 #define MICROPY_PY_STRUCT           (1)
 #define MICROPY_PY_SYS              (1)
+#define MICROPY_PY_SYS_MAXSIZE      (1)
 #define MICROPY_PY_SYS_EXIT         (1)
 #define MICROPY_PY_SYS_STDFILES     (1)
 #define MICROPY_PY_UBINASCII        (1)
@@ -41,7 +44,7 @@
 #define MICROPY_PY_UHASHLIB_SHA1    (1)
 #define MICROPY_PY_UJSON            (1)
 #define MICROPY_PY_MICROPYTHON_MEM_INFO (1)
-#define MICROPY_CPYTHON_COMPAT      (0)
+#define MICROPY_CPYTHON_COMPAT      (1)
 #define MICROPY_LONGINT_IMPL        (MICROPY_LONGINT_IMPL_MPZ)
 #define MICROPY_FLOAT_IMPL          (MICROPY_FLOAT_IMPL_FLOAT)
 #define MICROPY_ERROR_REPORTING     (MICROPY_ERROR_REPORTING_TERSE)
@@ -53,6 +56,8 @@
 
 #define MICROPY_MAKE_POINTER_CALLABLE(p) ((void*)((mp_uint_t)(p)))
 
+#define MP_SSIZE_MAX (0x7fffffff)
+
 #define UINT_FMT "%u"
 #define INT_FMT "%d"