Fix Fixnum deprecation warnings.

[patrickdavey]

Fixnum is being deprecated and merged with Bignum into Integer
(http://blog.bigbinary.com/2016/11/18/ruby-2-4-unifies-fixnum-and-bignum-into-integer.html)

This PR replaces Fixnum with Integer (in the tests) and fixes the
deprecation warnings

[brendon]

Excellent! :) Thanks @patrickdavey.

[krzysiek1507]

What's the file file:memdb1?mode=memory&cache=shared? ;)

[brendon]

I can't quite remember but you can use the blame feature of github to find out what the related commit was. I think it was to do with simulating race conditions.

[krzysiek1507]

It has been added with this PR and it looks like SQLite file.

[brendon]

Not according to the files list: https://github.com/swanandp/acts_as_list/pull/282/files

[krzysiek1507]

I can see it.

[brendon]

Ah I see! Sorry it doesn't really stand out at all in the list does it. I've committed a removal directly to master.

[krzysiek1507]

No problem! Thanks!

[patrickdavey]

My apologies for that :( I should have been more careful, usually am but it slipped through! Thanks @krzysiek1507 for pointing that out, and @brendon for fixing it.

[brendon]

Hey no worries :D We haven't released a gem yet anyway :)