Build modified streamline images

The official image from streamline does not currently work for the arm64
platform. As a temporary measure, the source code and docker build scripts
have been lifted from the official images and are used to build locally.

Some additional modifications are made to reduce overall image size, these
are documented in docker/README.md

docker/streamline-src/public/elite/bower_components/datatables-plugins/i18n/Galician.lang

@@ -0,0 +1,31 @@
+/**
+ * Galician translation
+ *  @name Galician
+ *  @anchor Galician
+ *  @author <i>Emilio</i>
+ */
+
+{
+	"sProcessing":     "Procesando...",
+	"sLengthMenu":     "Mostrar _MENU_ rexistros",
+	"sZeroRecords":    "Non se atoparon resultados",
+	"sEmptyTable":     "Ningún dato dispoñible nesta táboa",
+	"sInfo":           "Mostrando rexistros do _START_ ó _END_ dun total de _TOTAL_ rexistros",
+	"sInfoEmpty":      "Mostrando rexistros do 0 ó 0 dun total de 0 rexistros",
+	"sInfoFiltered":   "(filtrado dun total de _MAX_ rexistros)",
+	"sInfoPostFix":    "",
+	"sSearch":         "Buscar:",
+	"sUrl":            "",
+	"sInfoThousands":  ",",
+	"sLoadingRecords": "Cargando...",
+	"oPaginate": {
+		"sFirst":    "Primeiro",
+		"sLast":     "Último",
+		"sNext":     "Seguinte",
+		"sPrevious": "Anterior"
+	},
+	"oAria": {
+		"sSortAscending":  ": Activar para ordear a columna de maneira ascendente",
+		"sSortDescending": ": Activar para ordear a columna de maneira descendente"
+	}
+}