add several missing strings for join flow errors

src/l10n.json

@@ -2,6 +2,7 @@
     "general.accountSettings": "Account settings",
     "general.about": "About",
     "general.aboutScratch": "About Scratch",
+    "general.apiError": "Oops! Our server had an error.",
     "general.back": "Back",
     "general.birthMonth": "Birth Month",
     "general.birthYear": "Birth Year",
@@ -70,6 +71,7 @@
     "general.privacyPolicy": "Privacy Policy",
     "general.projects": "Projects",
     "general.profile": "Profile",
+    "general.required": "Required",
     "general.resourcesTitle": "Educator Resources",
     "general.scratchConference": "Scratch Conference",
     "general.scratchEd": "ScratchEd",
@@ -148,6 +150,8 @@
     "registration.choosePasswordStepTitle": "Create a password",
     "registration.choosePasswordStepTooltip": "Don't use your name or anything that's easy for someone else to guess.",
     "registration.classroomApiGeneralError": "Sorry, we could not find the registration information for this class",
+    "registration.countryStepDescription": "We’ll display your country on your profile.",
+    "registration.countryStepTitle": "What country do you live in?",
     "registration.generalError": "Sorry, an unexpected error occurred.",
     "registration.classroomInviteExistingStudentStepDescription": "you have been invited to join the class:",
     "registration.classroomInviteNewStudentStepDescription": "Your teacher has invited you to join a class:",
@@ -187,13 +191,15 @@
     "registration.usernameStepTitle": "Request a Teacher Account",
     "registration.usernameStepTitleScratcher": "Create a Scratch Account",
     "registration.validationMaxLength": "Sorry, you have exceeded the maximum character limit.",
-    "registration.validationPasswordLength": "Passwords must be at least six characters",
-    "registration.validationPasswordNotEquals": "Your password may not be \"password\"",
-    "registration.validationPasswordNotUsername": "Your password may not be your username",
+    "registration.validationPasswordConfirmNotEquals": "Passwords don’t match",
+    "registration.validationPasswordLength": "Must be 6 letters or longer",
+    "registration.validationPasswordNotEquals": "Password is too easy to guess. Try something else?",
+    "registration.validationPasswordNotUsername": "Password can’t match your username",
     "registration.validationUsernameRegexp": "Your username may only contain letters, numbers, \"-\", and \"_\"",
-    "registration.validationUsernameMinLength": "Usernames must be at least 3 characters",
-    "registration.validationUsernameMaxLength": "Usernames must be at most 20 characters",
-    "registration.validationUsernameExists": "Sorry, that username already exists",
+    "registration.validationUsernameMinLength": "Must be more than 3 letters long",
+    "registration.validationUsernameMaxLength": "“Must be fewer than 20 letters long",
+    "registration.validationUsernameExists": "Username taken. Try another?",
+    "registration.validationUsernameNotAllowed": "Username not allowed",
     "registration.validationUsernameVulgar": "Hmm, that looks inappropriate",
     "registration.validationUsernameInvalid": "Invalid username",
     "registration.validationEmailInvalid": "Email doesn’t look right. Try another?",