Calling boundingbox on a set of occurrences should ignore the occurrences with no coordinates

[tpoisot]

Currently, calculating the boundingbox for a set of occurrences returns a tuple with missing elements, if some occurrences do not have coordinates — this happens when GBIF requests don't use the hasCoordinate flag, for example.

So it seems like something should be wrapped into a skipmissing

This will most likely take place here:

SpeciesDistributionToolkit.jl/src/boundingbox.jl

Lines 18 to 22 in 1ddcffd

	function boundingbox(occ::AbstractOccurrenceCollection; padding=0.0)
	left, right = extrema(longitudes(occ))
	bottom, top = extrema(latitudes(occ))
	return _padbbox(left, right, bottom, top, padding)
	end

The lon/lat are returned from the following methods

SpeciesDistributionToolkit.jl/src/latlon.jl

Lines 1 to 19 in 1ddcffd

	"""
	longitudes(o::AbstractOccurrence)
	Returns the longitude for a single occurrence
	"""
	longitudes(o::T) where {T <: AbstractOccurrence} = ismissing(place(o)) ? missing : first(place(o))
	"""
	latitudes(o::AbstractOccurrence)
	Returns the latitude for a single occurrence
	"""
	latitudes(o::T) where {T <: AbstractOccurrence} = ismissing(place(o)) ? missing : last(place(o))
	longitudes(o::T) where {T <: AbstractOccurrenceCollection} = longitudes.(elements(o))
	latitudes(o::T) where {T <: AbstractOccurrenceCollection} = latitudes.(elements(o))
	longitudes(o::Vector{<:T}) where {T <: AbstractOccurrence} = longitudes.(o)
	latitudes(o::Vector{<:T}) where {T <: AbstractOccurrence} = latitudes.(o)