Add tasks for all the new languages

Task/Read-a-specific-line-from-a-file/Sidef/read-a-specific-line-from-a-file.sidef

@@ -0,0 +1,11 @@
+func getNthLine(filename, n) {
+  var file = File.new(filename);
+  file.open_r.each { |line|
+    Num($.) == n && return line;
+  }
+  warn "file #{file} does not have #{n} lines, only #{$.}\n";
+  return nil;
+}
+
+var line = getNthLine("/etc/passwd", 7);
+print line if defined line;