Bug 1062798 - Replace custom JSON loaders with LazyLoader.getJSON in SettingsApp

Replace various custom JSON loaders in SettingsApp with LazyLoader.getJSON.
Refactor code to handle promises where needed, and update tests to match.
Bug 977056 - [Dialer] Visual discrepancies: Call ended view under conference call participants list
Bug 1090501 - Remove 'busy'/'ready' event firing from previewStateChange event
Bug 1045820 - Port SimPicker implementation in MSAB and comms apps to GaiaSimPicker. r=gtorodelvalle, r=julienw, r=jmcf, r=rickychien
Bug 1095053 - remove --ui when invoking marionette-mocha
Merge pull request #25671 from DouglasSherk/1045820-sim-picker-dialer

Bug 1045820 - Port SimPicker implementation in MSAB and comms apps to GaiaSimPicker. r=gtorodelvalle, r=julienw, r=jmcf, r=rickychien
Merge pull request #24825 from gtorodelvalle/callscreen-bug-977056-participant-leaving-conference

Bug 977056 - [Dialer] Visual discrepancies: Call ended view under conference call participants list
Merge pull request #24791 from rjmackay/bug-1062798-settings-app-json-loading

Bug 1062798 - Replace custom JSON loaders with LazyLoader.getJSON in Settings App
Merge pull request #25893 from wilsonpage/1090501

Bug 1090501 - Remove 'busy'/'ready' event firing from previewStateChange event
1088813 - Calendar sending notifications with 'null' as body
Merge pull request #25633 from gaye/bug-1088813

Bug 1088813 - Calendar sending notifications with 'null' as body r=millermedeiros
Merge pull request #25898 from malini/uifix

Bug 1095053 - remove --ui when invoking marionette-mocha, r=eperelman