Merge pull request #2624 from EricDunsworth/v3.0-broken-link-fixes

Fixed broken links to ARB terms and conditions wiki pages.
Set pseudo-focused button background colours to !important in Grids SCSS. Prevents button-styled summaries from losing background colours on hover/focus when JS is disabled.
Tabbedinterface: fixed check for hidden child tab panels
Merge pull request #2655 from EricDunsworth/v3.0-grids-button-summary-bg

Set pseudo-focused button background colours to !important in Grids SCSS...
Merge pull request #2656 from patheard/nested-tabs

Tabbedinterface: fixed check for hidden child tab panels
i18n: grammar fix to session timeout message
Merge pull request #2658 from patheard/session-timeout-text

i18n: grammar fix to session timeout message
Tabbedinterface: mobile tab panel links can now change tab panels
Merge pull request #2660 from patheard/tab-content-links

Tabbedinterface: mobile tab panel links can now change tab panels
Ignore node_modules

Makes it easier while switching between the v3.0 & v3.1 builds now that v4.0 is using Node and Grunt. Backport from master
Tabbedinterface: keyboard switch of tabs stops cycle (fixes #2673)
Merge pull request #2679 from patheard/tab-cycle

Tabbedinterface: keyboard switch of tabs stops cycle (fixes #2673)
Tabbedinterface: fixes #2649 mobile create of nested tabbed interfaces
Merge pull request #2697 from patheard/tab-mobile

Tabbedinterface: fixes mobile creation of nested tabbed interfaces
Added spacing between the play button and the hidden text.
Fixed the duplicate mediaplayer ids
Merge pull request #2699 from LaurentGoderre/fix-multimedia-ids

Fixed the duplicate mediaplayer ids
Merge pull request #2688 from LaurentGoderre/v3.0

Tabbed interface: Added space between the visible text and hidden text
Share widget: Moved menu role to ul and added aria-haspopup to triggering button (#2680)
Merge pull request #2713 from pjackson28/sharewidgetfixes

Share widget: Moved menu role to ul and added aria-haspopup to triggering button (#2680)