spocc v0.4.0

NEW FEATURES

• New function as.vertnet() to coerce various inputs (e.g., result from occ(), occ2df(), or a key itself) to occurrence data objects (#142)
• occ() gains two parameters start and page to facilitate paging
  through results across data sources, instead of having to page
  individually for each data source. Some sources use the start parameter,
  while others use the page parameter. See Paging section in ?occ for
  details on Paging (#140)

MINOR IMPROVEMENTS

• Added Code of Conduct

BUG FIXES

• wkt_vis() now works with WKT polygons with multipe polygons, e.g.,
  spocc::wkt_vis("POLYGON((-125 38.4, -121.8 38.4, -121.8 40.9, -125 40.9, -125 38.4), (-115 22.4, -111.8 22.4, -111.8 30.9, -115 30.9, -115 22.4))") (#147)
• Fix to print.occdatind() to print more helpful info when a
  geometry search is used as opposed to a taxonomy based search (#149)
• Fix to print.occdatind() to not fail when first element not present;
  proceeds to next slot with data (#143)
• Fixed problem where occ() failed when multiple geometry elements
  passed in along with taxonomic names (#146)
• Fix to occ2df() for combining outputs to not fail when AntWeb
  doesn't give back dates (#144) (#145) - thanks @timcdlucas
• Fix to occ2df() to not fail when date field missing (#141)