L10n feedback for Firefox for iOS

[Stefan Arentz]

I filed the following bugs based on L10n feedback:

*Bug 1398148* <https://bugzilla.mozilla.org/show_bug.cgi?id=1398148> - Add
Custom Search Engine needs a better layout to support some locales
*Bug 1398146* <https://bugzilla.mozilla.org/show_bug.cgi?id=1398146> - New
Tab Context menus need shrinking text
*Bug 1398143* <https://bugzilla.mozilla.org/show_bug.cgi?id=1398143> - Tracking
Protection settings headers should not snap to the screen
*Bug 1398150* <https://bugzilla.mozilla.org/show_bug.cgi?id=1398150> - Some
intro slides have overlapping text

I moved them all into this sprint because we don't have a lot of time left
for L10n.

S.