add_bics_sector via fin data and bics_bridge data

[jacobvjk]

• My previous attempt to re-introduce bics sectors may produce duplicate entries in the portfolio due to non-unique bics entries.
• In this commit I revert to the original idea of using a bics_bridge file to map the holdings and bics sectors.
• the bridge is not complete yet and in general it seems unclear if it is a great choice to use bics, but for the time being, I guess we no alternatives, as this is promised to be part of pacta 2020 afaik.

[jacobvjk]

I also tried to finally get rid of these horrendous .DS_Store files but, although they are in my .gitignore file, they keep returning and somehow mess up this PR... @maurolepore I'm sure you know what I'm not seeing here?

[maurolepore]

Try usethis::git_vaccinate(): https://usethis.r-lib.org/reference/git_vaccinate.html

[jacobvjk]

Still not really working.. I mean I don't understand how this is a conflict anyway..

[maurolepore]

Now re-reading this thread: https://github.com/2DegreesInvesting/resources/issues/115
...

[maurolepore]

So it looks like CJ's last comment is your best bet: https://github.com/2DegreesInvesting/resources/issues/115#issuecomment-608579867

I think:

git config --global core.excludesfile .DS_Store

[jacobvjk]

tired the last one, but this was messy, so I quickly moved it all to a new branch and new PR #78... Closing this one.