Work around bug 1098470 by detecting manifest.* with getFeature (bug 1097424)

In Firefox OS 2.0 and 2.1 (possibly 2.2 if the bug isn't fixed soon),
hasFeature(manifest.*) will fail, but getFeature(manifest.*) will work.
add "Fireplace" heading to README
change screenshot in README (imgur → GitHub)
fix nav buttons for fxOS2.2 (bug 1095709)
reset the offset after switching between mkt/settings navbars
Merge pull request #824 from diox/workaround-has-feature-manifest-yulelog

Work around bug 1098470 by detecting manifest.* with getFeature (bug 1097424)
Merge pull request #825 from ngokevin/navbartweak23

fix nav buttons for fxOS2.2, reset offset switching between navbars
set href on nav switcher buttons (bug 1095709)
marketplace-core-modules v1.0.11
bump gulp/commonplace to switch api settings (bug 1099350)
Set the native-fxa class for native yulelog FxA (bug 1101751)
Merge pull request #826 from mstriemer/no-sign-out-yulelog-fxa-1101751

Hide Sign Out button with native yulelog FxA (bug 1101751)
Include some help text on the FxA email form (bug 1095626)
Workaround for Firefox 0S 2.0 which has getFeature(), not hasFeature() (bug 1097424)
Merge pull request #827 from mstriemer/transition-help-text-1095626

Include some help text on the FxA email form (bug 1095626)
Commit from Mozilla Verbatim by user joergenr@stofanet.dk.: 325 of 335 strings translated (0 fuzzy).
Merge branch 'master' of github.com:mozilla/fireplace
Revert "make compat filtering smaller on desktop (bug 1093936)"

This reverts commit 18533e610bb8882751e2ab57dd158e403950b66f.

It caused a regression (truncated text), bug 1102929
move from codenames in README
marketplace-core-modules v1.0.12