docs(all): fixes typos and improves readability
fix(views): respect icon_sizes config values when rendering icons

Remove hard-coded references to available icons sizes and use global icon_sizes config values and keys instead
Merge pull request #7088 from hypeJunction/icon-sizes

fix(views): respect icon_sizes config values when rendering icons
docs(cron): adds RST documentation about cron jobs

Converts wiki cron page to RST and references cron in Upgrading docs

Refs #6884
docs(all): improves formatting and comprehensibility of docs

Reworded some paragraphs to make more sense to new users. Applied formatting to some lists and paragraphs
Merge pull request #7087 from hypeJunction/docs

Fixes typos and adds cron RST docs
fix(embed): Manually load CSS/JS libs for embed when editing comments on the activity page.

Fixes #6422
Merge pull request #7107 from brettp/embed_activity_ajax

fix(embed): Manually load CSS/JS libs for embed when editing comments on...
fix(embed): Checking for lightbox and embed before loading JS libs when requested through AJAX.

Refs #7107.
fix(walled_garden): ACCESS_PUBLIC no longer available in group context

When walled garden is enabled ACCESS_PUBLIC is removed from the access
options, except in the group context. This fix also removes it for the
group context.
fix(groups): removes ACCESS_PUBLIC from visibility options if walled
garden is enabled

In a walled garden site nothing is allowed to be public, this also
applies to the visibility of groups
Merge pull request #7038 from jeabakker/group-visibility-walled-garden

fix(groups): removes ACCESS_PUBLIC from visibility options if walled garden is enabled
Merge pull request #7035 from jeabakker/groups-walled-garden

fix(walled_garden): ACCESS_PUBLIC no longer available in group context
Merge pull request #7109 from brettp/embed_activity_ajax2

fix(embed): Checking for lightbox and embed before loading JS libs when ...
Merge pull request #7127 from Elgg/1.9

Merge 1.9 up to 1.x
chore(filesystem): Convert filesystem to Gaufrette and add tests

Flysystem requires PHP 5.4 and we're not *quite* ready for that just yet...
Merge pull request #7132 from ewinslow/gaufrette

chore(filesystem): Convert filesystem to Gaufrette and add tests
chore(input): merge `get_input` and `set_input` into `Elgg\Http\Request`

Fixes #7091