Merge branch '4.4' into 5.1

* 4.4:
  [Mailer] Fixed mandrill api header structure
  [HttpClient][ResponseTrait] Fix typo
  [Mailer] Reorder headers used to determine Sender
  [Validator] Add Lithuanian translation for ISIN constraint

Author: fabpot

Resources/translations/validators.lt.xlf

@@ -382,6 +382,10 @@
                 <source>Each element of this collection should satisfy its own set of constraints.</source>
                 <target>Kiekvienas šio sąrašo elementas turi atitikti savo nurodymų rinkinį.</target>
             </trans-unit>
+            <trans-unit id="99">
+                <source>This value is not a valid International Securities Identification Number (ISIN).</source>
+                <target>Ši reišmė neatitinka tarptautinio vertybinių popierių identifikavimo numerio formato (ISIN).</target>
+            </trans-unit>
         </body>
     </file>
 </xliff>