New features about cartography

[dieghernan]

In the case that the PR would be accepted, next steps would be:

• Add new functions to /_pkgdown.yml
• Add new functions to /R/Package.R
• roxygen2::roxygenize()
• pkgdown::build_reference_index()
• pkgdown::build_reference()

Happy to work also on a vignette, but I think in terms of use test that it would be interesting that another person would do that, in order to stress the functions.

[rCarto]

Wow this is very nice! And *pngLayer() function comes as a good surprise :-)

As you have seen, v2.3.0 is really recent, so there is no hurry, but I would be very happy to accept a PR.
I would be glad to add documentation on these function in the vignette.

[dieghernan]

On it, I would let know, also another good surprise is coming,

By the way, speaking of hatchedLayer, see comments here: https://stackoverflow.com/questions/21677489/fill-geospatial-polygons-with-pattern-r/59301874#59301874

[dieghernan]

Hi! I am finishing another function named wordcloudLayer. It is an adaptation of wordcloud package by @ifellows, and it is a layer in the middle of labelLayer and choroLayer.

I used the is_overlap function, and basically it draws a Wordcloud using the shape of an sf object. See here a description and a potential outcome.

I am working on a extended vignette to show how this function could be useful and stunning at the same time.

[rCarto]

fix by #63

[ifellows]

@dieghernan , looks cool. Thank you for providing authorship attribution.