pinned down error code enum values

Note : all error codes are changed by this new version,
but it's expected to be the last change for existing codes.

Codes are now grouped by category, and receive a manually attributed value.
The objective is to guarantee that
error code values will not change in the future
when introducing new codes.
Intentionnal empty spaces and ranges are defined
in order to keep room for potential new codes.

lib/legacy/zstd_v04.c

@@ -2776,7 +2776,7 @@ static size_t ZSTD_decodeFrameHeader_Part2(ZSTD_DCtx* zc, const void* src, size_
     size_t result;
     if (srcSize != zc->headerSize) return ERROR(srcSize_wrong);
     result = ZSTD_getFrameParams(&(zc->params), src, srcSize);
-    if ((MEM_32bits()) && (zc->params.windowLog > 25)) return ERROR(frameParameter_unsupportedBy32bits);
+    if ((MEM_32bits()) && (zc->params.windowLog > 25)) return ERROR(frameParameter_unsupported);
     return result;
 }