Fix translatable string for "Injected File Path Bytes"

Change-Id: I7a60c371621bd37d1918db7ddcabd4cb2dcd9d0d
Closes-Bug: #1254049
(cherry picked from commit 39d3b8418ae0d4827571bcbbe5d79daedaaa053b)
Add contextual markers to BatchAction messages

BatchAction message is used for both present (table action menu)
and past (completion message) and there is no way that translators
use different texts for present and passt messages.
This commit add contextual markers to the message strings and allows
translators to use different texts for message in BatchAction.

Change-Id: Ie6438730386fc2cca18704354d5cf5f5b71cd494
Closes-Bug: #1252082
(cherry picked from commit 9e6d59bc8b7811622e42ebdcb5911eb6487a4f77)
Add extra extension file to makemessage command line

specify the file extensions of the makemessage to *.html, *.txt, *.csv

Closes-Bug: #1226910
(cherry picked from commit 0b03a7fdea3d6586ec2c22783e309bb75d68fdc5)

The above fix introduces an extra bug when updating POT files, so
the commit below is also cherry-picked.
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Fix warning in run_tests.sh --makemessages

Specify --extension=html,txt,csv only for openstack_dashboard.
For djangojs, --extension should be 'js'.
This is the cause of the warning.

Closes-Bug: #1243526
(cherry picked from commit 79ae2139bb2f458de698aa116270428f54e22dc6)
----

This patch does not update POT files for stable/havana.
They will be updated in a single patch.

Change-Id: I115cd448249ac0b1b27a6b28fca3f16d6b2670a6
Merge "Fix translatable string for "Injected File Path Bytes"" into stable/havana
Merge "Add extra extension file to makemessage command line" into stable/havana
Merge "Add contextual markers to BatchAction messages" into stable/havana
Merge branch 'stable/havana' of https://github.com/openstack/horizon into stable/havana_routerrules