prevent trying to setState on unmounted VirtualList + checking for undefined state before comparison

[Ramshackle-Jamathon]

fixes #59
fixes #65

[Ramshackle-Jamathon]

@developerdizzle sorry if this PR is a bit abrupt, I just wanted to fix some of the warnings/errors I ran into using this super rad component!

[Ramshackle-Jamathon]

@developerdizzle yoooo! you mind taking a look-see at this PR some time?

[developerdizzle]

@Ramshackle-Jamathon Can you add a patch version bump in package.json?

[konradd93]

Still not working, becouse you changed only file src/VirtualList.js, but in package.json is "main": "lib/VirtualList.js".
Next time check your change really solve the problem before creating the pull request, please. ;)

[Ramshackle-Jamathon]

@konradd93 my bad dude, I did check that my changes fixed the problem but I didn't include the build artifacts in my PR (the lib/ directory you're talking about). I should've ran the build when I pushed the version bump.

@developerdizzle It should be resolved by running the build and releasing a patch

[konradd93]

"@developerdizzle It should be resolved by running the build and releasing a patch"

@developerdizzle, can you do that?

[mikechabot]

Any progress on this? Folks are noticing a version mismatch: #72

[developerdizzle]

Version 2.2.4 has been published! My apologies for the delay.

[mikechabot]

@developerdizzle You rock!