message: fix document about HoughLines
diff: @@ -1947,10 +1947,10 @@ transform.
  @param image 8-bit, single-channel binary source image. The image may be modified by the function.
  @param lines Output vector of lines. Each line is represented by a 2 or 3 element vector
  -\f$(\rho, \theta)\f$ or \f$(\rho, \theta, \votes)\f$ . \f$\rho\f$ is the distance from the coordinate origin \f$(0,0)\f$ (top-left corner of
  +\f$(\rho, \theta)\f$ or \f$(\rho, \theta, \textrm{votes})\f$ . \f$\rho\f$ is the distance from the coordinate origin \f$(0,0)\f$ (top-left corner of
  the image). \f$\theta\f$ is the line rotation angle in radians (
  \f$0 \sim \textrm{vertical line}, \pi/2 \sim \textrm{horizontal line}\f$ ).
  -\f$\votes\f$ is the value of accumulator.
  +\f$\textrm{votes}\f$ is the value of accumulator.
  @param rho Distance resolution of the accumulator in pixels.
  @param theta Angle resolution of the accumulator in radians.
  @param threshold Accumulator threshold parameter. Only those lines are returned that get enough
  