Changes in new version

Version KarsTS 2.3 (June 7, 2020)
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- A function to upsample time series was added (the previous version only allowed downsampling)
- Functions to build and plot fixed amount of neighbors recurrence matrices were added.
- Now the user can choose the resolution that will be used when saving the plots to image files. 
- The examples were edited. 
- The button MCAR Little's test was removed