Update CHANGELOG.md

Merge pull request #792 from hyperoslo/implement/size-cache-for-ios

Populate sizeCache on iOS

Merge pull request #789 from hyperoslo/fix/focused-item-index-bug

Set focused item index to zero if index is nil when updating the delegates

Merge pull request #788 from hyperoslo/remove/unwanted-print

Remove unwanted print statement

Bump version to 7.4.0

Bump version to 7.3.0

Bump version to 7.2.1

Bump version to 7.2.0

Update Spots.podspec

Bump the build number