Bug 1019993 - Correct compositekey to compositeKey

Replace compositekey with compositeKey to follow interCaps coding
style guidelines.
Bug 1017918 - Add mai (Maithili) to Gaia languages
Bug 1022939 - Add ARIA markup for gaia-radio and give example for radio menu items.
Bug 1016393 - [Camera] Fix unit tests with a newer mocha
Bug 981674 - [Contacts] Contact's name merged to another one previously then exported to sd card and imported again, is not shown fine
Bug 1020471 - WebrtcClient is not defined
Bug 1023046 - Finetune app to app tranisiton by ordering
Bug 1023238 - Remember my choice is not the default option pre-selected in GUM permission
Bug 1022475 - (Part I) Implement InputAppsTransitionManager
Bug 1022475 - (Part II) Let KeyboardManager use it
Bug 1022475 - (Part III) Fix JS marionette tests
Bug 1022475 - (Part VI) Fix Python tests
Bug 1013207 - [Keyboard][Performance] Lazily load l10n.js
Merge pull request #20333 from timdream/input-manage-transition3

Bug 1022475 - Organizing keyboard transition management to another script, r=rudyl
Merge pull request #20261 from alivedise/bugzilla/1023046_2.1/app2app-transition-finetune

Bug 1023046 - Finetune app to app tranisiton by ordering, r=timdream
Merge pull request #20287 from timdream/keyboard-lazily-l10n2

Bug 1013207 - [Keyboard][Performance] Lazily load l10n.js, r=rudyl
Merge pull request #20329 from gasolin/issue-1023238

Bug 1023238 - Remember my choice is not the default option pre-selected ..., r=alive
Merge pull request #20238 from fcampo/import-merged-981674

Bug 981674 - [Contacts] Merged-name-contact imported is not is not shown fine (r=jmcf)
Bug 1008987 - [Contacts][Merger] Thumbnail on contacts list disappear when importing same vCard/.vcf file several times
Merge pull request #19761 from wilsonpage/1016393

Bug 1016393 - [Camera] Fix unit tests with a newer mocha