feature(views): allows rendering empty results using an anonymous function

If you want the no_results message to not be wrapped by P tags, or you don’t
want to always incur the cost of rendering a view for backup content, you
can now provide a Closure whose output will be echoed by the view.
chore(tagcloud): move site tagcloud functionality to the tagcloud plugin

fixes #7140
chore(tagcloud): moved tagcloud theme sandbox output to tagcloud plugin
chore(tagcloud): moved tagcloud related views to tagcloud plugin
chore(services): Add missing property doc for entityTable
Merge pull request #7548 from mrclay/dic_entityTable

chore(services): Add missing property doc for entityTable
fix(ckeditor): ckeditor now prevents image drag/drop/paste in editor

fixes #4970
feature(js): extended the usability of rel="toggle"

It is now possible to toggle multiple elements with an completely custom
selector and you can control the toggle effect (slide or direct
hide/show).

This helps for #7508, reduces the need for #5139 and fixes #3070.
chore(tagcloud): moved tagcloud related language strings to plugin
chore(tagcloud): moved tagcloud related css to tagcloud plugin
Merge pull request #7507 from jdalsem/block-ckeditor-image-drop

fix(plugins): ckeditor now prevents image drag/drop/paste in editor
Merge pull request #7538 from jdalsem/improve-toggle-js

feature(js): extended the usability of rel="toggle"
Merge pull request #7510 from jdalsem/move-tagcloud-out-of-core

Move tagcloud out of core
feature(cache): allows using ints as keys in Cache\Pool

Keying based on GUIDs is a common case, we should not require devs to
explicitly cast when using pool. There’s too much risk for errors to
auto-casting floats/bools though.
Merge pull request #7554 from mrclay/cache_keys

feature(cache): allows using ints as keys in Cache\Pool
fix(forms): Login and account forms widened and centered by default

Fixes #6456
Merge pull request #7560 from ewinslow/forms-max-width

fix(forms): Login and account forms widened and centered by default
deprecate(libraries): undeprecate the elgg_register/load_library functions

This reverts commit 190b69216e889274621b3ca15b5055c605b1067c.
chore(libraries): update library loading functions to use config service
chore(services): add missing property declarations on service provider