Update the plotting functionality of the package:

   * PlotHR, PlotNIHR and PlotSpectrogram now accept as arguments title, xlab, ylab and other usual plotting parameters.
  * PlotSpectrogram is able to plot episodic information. The private function rhrv.filled.contour has been added in order to give support to this function.
   * OverplotEpisodes is a new function that is able to plot the episodic information over any plot of a time series.
  * PlotSinglePowerBand is a new function that plots a specific power band. This function accepts typical R plotting arguments so it's intended to give flexibility to the user.

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/rhrv@143 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Duplicated beats are removed in wfdb files



git-svn-id: svn://svn.r-forge.r-project.org/svnroot/rhrv@144 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Adding two new video tutorials to the RHRV web (nonlinear analysis and episode analysis)

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/rhrv@145 edb9625f-4e0d-4859-8d74-9fd3b1da38cb