New translations Spanish from Crowdin [skip ci]

po/es_ES.po

@@ -3,7 +3,7 @@ msgstr ""
 "Project-Id-Version: xournalpp\n"
 "Report-Msgid-Bugs-To: \n"
 "POT-Creation-Date: 2019-08-27 05:08+0000\n"
-"PO-Revision-Date: 2019-08-27 05:16\n"
+"PO-Revision-Date: 2019-08-27 18:03\n"
 "Last-Translator: Ulrich Huber (LittleHuba)\n"
 "Language-Team: Spanish\n"
 "Language: es_ES\n"
@@ -1471,7 +1471,7 @@ msgstr "xoj-preview-extractor: invóquelo con ENTRADA.xoj SALIDA.png"
 
 #: ../src/xoj-preview-extractor/xournal-thumbnailer.cpp:158
 msgid "xoj-preview-extractor: could not find icon \"{1}\""
-msgstr ""
+msgstr "xoj-preview-extractor: no se pudo encontrar el icono «{1}»"
 
 #: ../src/xoj-preview-extractor/xournal-thumbnailer.cpp:102
 msgid "xoj-preview-extractor: file \"{1}\" contains no preview"