Add tasks for all the new languages

Task/Here-document/Sidef/here-document-1.sidef

@@ -0,0 +1,4 @@
+var text = <<"EOF";
+a = #{1+2}
+b = #{3+4}
+EOF

Task/Here-document/Sidef/here-document-2.sidef

@@ -0,0 +1,5 @@
+var x = <<'FOO';
+No
+#{interpolation}
+here
+FOO

Task/Here-document/Sidef/here-document-3.sidef

@@ -0,0 +1,4 @@
+say (<<EOF + "lamb");
+Mary had
+  a little
+EOF

Task/Here-document/Sidef/here-document-4.sidef

@@ -0,0 +1,5 @@
+say (<<EOF
+Mary had
+  a little
+EOF
++ "lamb");