Add a warning to first run introduction about this being a pre-release (

#275)

* Add a warning to first run introduction
Fixes #270 requested by @sandysage  to explain features may change and data may not be retained between releases

* missing a word

* Better semantics for important message

* Clearer warning, doesn't bury lede, not as scary

* Quick hack to get strong tag output after localization happens

src/webextension/firstrun/components/welcome.js

@@ -20,6 +20,15 @@ export default function Welcome() {
         adipiscing elit. Etiam porta sem malesuada magna mollis euismod. Cras
         mattis consectetur purus sit amet fermentum.</p>
       </Localized>
+      <p>
+        <Localized id="welcome-warning">
+          <strong>Lorem ipsum dolor sit amet, consectetur.
+          Mauris, aliquam vel pellentesque et, mattis bibendum tellus. Fusce
+          sodales, tellus a auctor accumsan, diam risus pharetra orci, at lacinia
+          libero eros ut erat. Fusce ex neque, pharetra id rhoncus in,
+          pellentesque quis urna.</strong>
+        </Localized>
+      </p>
       <Localized id="welcome-feedback">
         <p>Curabitur blandit tempus porttitor. Nulla vitae elit libero, a
         pharetra augue. Vestibulum id ligula porta felis euismod semper.

src/webextension/locales/en-US/firstrun.ftl

@@ -9,10 +9,14 @@ welcome-intro =
     new entries, and then later you can view, search, edit, and
     delete those entries.
 
+welcome-warning =
+    This is a rapidly evolving prototype that will change as Alpha progresses.
+    Any data stored here is not guaranteed to be retained in future updates.
+
 welcome-feedback =
     Please be sure to let us know your thoughts using our feedback
     button within the tool, including any issues you may find, things
-    you like, and the things you're looking forward in the future.
+    you like, and the things you're looking forward to in the future.
 
 master-password-setup-formtitle = Please create a master password below: