Memory leaks

[jezwhite]

Fix for #27 and a few other minor memory leaks

[jezwhite]

Ok, this PR has issues.

I've been running this branch in a production environment for a the last week and the leak fixes have made a huge difference on memory consumption. However, I have had a couple of random crashes. The crashes are related to #28. What is happening is that depending on what order the containers are destroyed, the SV's for output/errors no longer exist which then causes the crash. In the base branch, the SV's for output/errors are never freed, so no crash. I will work on a fix.

[gonzus]

Hey, thanks for the PR and comments. I was away for a while, but I will be happy to review and merge once you declare the fixes done. Cheers!

[jezwhite]

Ok, added another commit, with an additional test. Straightforward enough change, but you may have issues with the way I stored the Duk pointer into the ctx instance, but I think it's the 'best' way?

/* save our duk pointer to the ctx so it can get it back later when we do callbacks */
duk_push_thread_stash(duk->ctx,duk->ctx);
duk_push_pointer(duk->ctx, duk);
duk_put_prop_string(duk->ctx, -2, PL_NAME_CONSOLE_GENERIC_CALLBACK); 
duk_pop(duk->ctx);

/* Get our duk pointer for this ctx*/
duk_push_thread_stash(ctx,ctx);
duk_get_prop_string(ctx, -1, PL_NAME_CONSOLE_GENERIC_CALLBACK); 
ourData = duk_get_pointer(ctx, -1);
duk_pop(ctx);

#define PL_NAME_CONSOLE_GENERIC_CALLBACK  "__perl__duk__"

Any questions, comments, let me know.

[gonzus]

Merged more or less blindly -- let me know if anything broke. Thanks!