Release/v2.3.0

[kimberscott]

Release 2.3.0:

• Upgrade from node 8 -> 10
• Prepare for translation of frames using ember-intl; labs that want to test in a language other than English can now provide Lookit with a translation file based on translations/en_us.yaml, then specify the language using a "language" parameter on the first frame.
• Allow use of videos rather than images in exp-lookit-change-detection and allow stream-specific timings (Modify exp-lookit-change-detection so 1) image streams can also show video and 2) display time can be set to differ for each image category #183)
• Additional customization of consent template 5 and exit survey where required by researchers' IRBs (Further customization of consent template 5 & exit survey for Northwestern IRB #211)
• Provide option to get consent from adult only (not on behalf of a child) (Allow selection of an adult-only consent prompt #218)
• Minor fixes to docs
• Allow customization of text & progress bar on exp-lookit-start-recording & exp-lookit-stop-recording frames (Customize "establishing video connection" display on exp-lookit-start-recording and exp-lookit-stop-recording frames #214)
• Remove extra orange box explaining options upon closing window - just put directions in the "exit" box.
• Relabel the "refresh webcam" button on exp-video-config so people are less likely to refresh the page or press the refresh button under the webcam view instead (Clarify exp-video-config "refresh webcam" button #207)
• Bugfix: Stop audio from pauseVideo and waitForUploadVideo when they're not being displayed (Stop audio of "waitForUploadVideo" from continuing into test video #217)
• Store screen resolution during exp-video-config frame (Store screen resolution in exp-video-config frame #210)
• Pre-load images before displaying any in exp-lookit-images-audio (Preload images/audio on exp-lookit-images-audio page #206)
• Show optional visual indicator of whether child is looking in -infant-control frames; allow delaying measurement period relative to stimulus onset (Infant-controlled trials with help from parents #143)