Added an additional call: `SDL_SetEventHandler()` to SDL.
This is not in the official API but it is needed for Mozilla
Persona, which makes sure an event handler is on the stack when
`navigator.id.request()` is called.

Using the standard SDL api, this can never be the case because an SDL
app retrieves events from SDL’s event queue independently of when
those events are added to the queue (through event handlers that SDL
itself registers).

With this additional call, apps can receive events directly in
response to an actual event handler which will still be on the stack
when the event is handled by the SDL-based application.
Rename SDL_SetEventHandler from previous commit to emscripten_SDL_SetEventHandler to reflect that this is our extension, and add comments.
Add test for emscripten_SDL_SetEventHandler.
Fix ffdb issue when taking a screenshot and the screenshot is small enough to fit into a single message instead of having multiple fragments.
Add support for printing FFOS device system description fields (deviceActor getDescription verb) with 'ffdb.py desc'
Add support for printing out a memory summary of a running application with ffdb via 'ffdb.py memory <app>'.
We don't seem to have tests for --js-library in core suite, so move other.test_js_libraries to the core test suite so that it gets tested in all modes.
Merge pull request #2412 from juj/test_js_libraries_in_core

Test js libraries in core
Merge pull request #2417 from juj/emscripten_SDL_SetEventHandler

Emscripten sdl set event handler
Improve Ctrl-C exception detection to cover the whole ffdb.py app.
Hide false warnings in 'ffdb.py install --run --log' if app was not installed or running before.
DETERMINISTIC option
LIBRARY_DEBUG fix
fix bug introduced in 92cab32f5f where we ignore the current offset in a file when writing initial data to it
add test for d2768d2ee
add sqlite speed test
change value of position after seeking
add myself to AUTHORS
add test case for checking file append
Merge pull request #2424 from gsathya/fix_append_bug

Fix append bug