allow adding several packages at once using `CondaPkg.add`

[schlichtanders]

This currently fails, which is quite disappointing

Looking into the code, it is just not supported to pass a Vector of String. Passing a Vector of PkgSpec works, but this is very lowlevel and should not be needed.

[schlichtanders]

My workaround is now

CondaPkg.add(CondaPkg.PkgREPL.parse_pkg.(["numpy", "pandas", "matplotlib", "plotly"]))

It looks like this is not intended usage unfortunately.

Hence it would be really great if CondaPkg.add(["numpy", "pandas", "matplotlib", "plotly"]) just works

[cjdoris]

I'll think about adding that.

In the meantime, you can do

CondaPkg.add.([...], resolve=false)
CondaPkg.resolve()