requests about more metadata on the variables

[jerabaul29]

From the data management group:

"
If you do not have standard_name for variables, please always add long_name. "Unit " should be "units". I'm getting quite few errors when trying to validate (https://compliance.ioos.us/index.html), and I can't visualize in panoply. Are your data supposed to be visualised as trajectory?
"

I guess this should be part of trajan so this is automatically done? :) I will try to add this in a PR :) .

[jerabaul29]

Also from them:

"
"Unit " should be "units".
"

[gauteh]

Related to: #78 and #90.

[knutfrode]

Yes, I corrected now attribute name unit to units at several places in the code:
#101

Otherwise I believe standard_name attributes should be correct for the core variables (e.g. lontitude, latitude, time), however seems to be missing for the more specialized variables e.g. in reader_omb (#78)

[jerabaul29]

Should be fixed in PR #102 for the OMB reader :) .

[gauteh]

I think a bunch of them have standard names, it is just that I wrote long_name rather than standard_name in the sfy code.

[gauteh]

the frequency bins should be a coordinate variable to the spectrum.

[jerabaul29]

I have used standard names where I could find them, and long names when I had to make custom stuff :) .