Migrating from libnetcdf to ncdf4

[sneumann]

Hi, to avoid the recurring Linking Hell with HDF5 and netCDF,
we could drop https://github.com/sneumann/mzR/blob/master/src/rnetCDF.c
and rewrite https://github.com/sneumann/mzR/blob/master/R/methods-mzRnetCDF.R
to use https://cran.r-project.org/package=ncdf4 instead.
Yours, Steffen

[lgatto]

I would definitely be in favour of re-using the ncdf4 package to limit external dependencies on our direct end, but won't be able to commit time to rewrite the mzRnetCDF methods.

[sneumann]

I have a first go at dfbd825
please beat it and report shortcomings before we can cleanup and merge