Fix FS.h error and add early exit option to DRAW callback

This release adds the ability to cleanly stop decoding an image at an arbitrary point of the decode. Let's say that an image is too large for your display and only a portion can be displayed; the DRAW callback can now return 0/false to indicate that decoding should stop.

Also in this release is a compiler fix for ESP32 relating to the inclusion of FS.h for SD card access