code: @Nonnull
    public BootstrapSpacingBuilder property (@Nonnull final EBootstrapSpacingPropertyType eProperty)
    {
      ValueEnforcer.notNull (eProperty, "Property");
      m_eProperty = eProperty;
      return this;
    }
docs: Set the property type. Default is "margin".
  
  @param eProperty
  Property type. May not be <code>null</code>.
  @return this for chaining