Bindep cleanup and JavaScript updates

Adjust for the Py3K-only present by dropping some Python 2.7 package
names which are no longer available on our test platforms, and
adjusting others to their newer Python 3.x versions. Also some
Debian-specific fixups like moving from iceweasel back to firefox
and the locales package becoming essential.

Apply a `yarn upgrade` result for the yarn.lock file since some of
the dependency versions included there were too old to work with
Python 3 yet.

Change-Id: I1da3ac6f7bfbaa6dc75f6171f0055c8730f0ed43

bindep.txt

@@ -7,16 +7,14 @@ chromium-browser [platform:dpkg test]
 curl
 cyrus-sasl-devel [platform:rpm]
 dbus
-firefox [!platform:debian test]
+firefox [test]
 gawk
 gettext [test]
-iceweasel [platform:debian test]
 language-pack-en [platform:ubuntu]
 libcurl-devel [platform:rpm]
 libcurl4-gnutls-dev [platform:dpkg]
 libmysqlclient-dev [platform:dpkg]
 libpq-dev [platform:dpkg]
-locales [platform:debian]
 lsb-release [test]
 mariadb [platform:rpm]
 mariadb-devel [platform:rpm]
@@ -30,16 +28,11 @@ postgresql
 postgresql-client [platform:dpkg]
 postgresql-devel [platform:rpm]
 postgresql-server [platform:rpm]
-python-dev [platform:dpkg]
-python-devel [platform:rpm]
-python-lxml
-python-zmq
 python3-all-dev [platform:ubuntu !platform:ubuntu-precise]
 python3-dev [platform:dpkg]
 python3-devel [platform:fedora]
-python3.4 [platform:ubuntu-trusty]
-python3.5 [platform:ubuntu-xenial]
-python34-devel [platform:centos]
+python3-lxml
+python3-zmq
 sqlite [platform:rpm]
 sqlite-devel [platform:rpm]
 sqlite3 [platform:dpkg]