Merge branch 'rework'

content/guides/sandstone/_index.md

content/quickstarts/_index.md

content/quickstarts/hpc_intro.md

content/quickstarts/setting_up_and_using_duo.md

static/images/5832716.png

static/images/5832717.png

static/images/DUOApprove.jpg

static/images/DUORequest.jpg

static/images/SandstoneJobConf.png

static/images/SandstoneSA.png

static/images/SandstoneSASettings.png

static/images/SandstoneSAStatus.png

static/images/SandstoneSAStatusPage.png

static/images/SandstoneSAStatuses.png

static/images/SandstoneTerminal.png

static/images/Sandstoneeditor.png

static/images/SandstoneedtiorDropDown.png

static/images/SandstonefileBrowserOver.png

static/images/SandstonefileOptions.png