Instagram Feed Pro 6.4

* Tweak: Changed screen reader and alt text to be more SEO friendly (change made to item.php template).
* Tweak: Added PHP hooks to use custom alt and screen reader text.
* Fix: Screen reader text would be visible if text was right aligned.
* Fix: Feeds were not updating when background caching used.
* Fix: Incorrect image resolution would be used when setting the image resolution to something other than auto.

* New: Added a close button for the share feature in the lightbox.
* New: Added aria-label attributes to svgs for improved accessibility.
* Tweak: Removed Google Plus as a share option.
* Tweak: Error reporting improved. Information about errors encountered while retrieving posts now more concise.
* Fix: Improved reliablity of touch detection for opening the lightbox with touch devices.
* Fix: Minified version of CSS file was not actually minified.

* Tweak: Check added to make sure sbiOwlCarousel was defined before using to show carousel posts in the lightbox added.
* Tweak: Added a default set of options of sb_instagram_js_options not defined on the page.
* Tweak: Added a text link in the settings page footer to our new free [YouTube feed](https://wordpress.org/plugins/feeds-for-youtube/) plugin
* Fix: Part of the next image in the carousel would display when opening carousel posts in the lightbox on slower networks.
* Fix: Added a workaround for error caused by videos in stories displayed in the lightbox not having thumbnails available.