jooby/src/main/java/org/jooby/Result.java
@Nonnull
  public Result header(final String name, final Object value) {
    requireNonNull(name, "Header's name is required.");
    requireNonNull(value, "Header's value is required.");
    setHeader(name, value);
    return this;
  }
@Nonnull
  public Result header(final String name, final Object value) {
    requireNonNull(name, "Header's name is required.");
    requireNonNull(value, "Header's value is required.");
    setHeader(name, value);
    return this;
  }
Sets a response header with the given name and value. If the header had already been set,
the new value overwrites the previous one.

@param name Header's name.
@param value Header's value.
@return This content.