Add multiple NUTs mappings to LAU data

[adibaba]

Some LAU source files include multiple NUTs mappings as stated in the following table:

https://ec.europa.eu/eurostat/web/nuts/local-administrative-units

Tables	Provisional/ Validated	Year	Links
Correspondence table LAU – NUTS 2021, EU-27 and EFTA / available Candidate Countries	Provisional	2021
Correspondence table LAU – NUTS 2016/2021, EU-27, UK and EFTA / available Candidate Countries	Provisional	2020
Correspondence table LAU – NUTS 2016, EU-28 and EFTA / available Candidate Countries	Validated	2019
Correspondence table LAU – NUTS 2016, EU-28 and EFTA / available Candidate Countries	Validated	2018
Correspondence table LAU – NUTS 2016, EU-28 and EFTA / available Candidate Countries	Validated	2017
Correspondence table LAU – NUTS 2013, EU-28 and EFTA / available Candidate Countries	Validated	2017
Correspondence table LAU 2 – NUTS 2013, EU-28	Validated	2016
Correspondence table LAU 2 – NUTS 2013, EU-28	Validated	2015
Correspondence table LAU 2 – NUTS 2013, EU-28	Validated	2014
Correspondence table LAU 2 – NUTS 2013 /NUTS 2010, EU-28	Validated	2013
Correspondence table LAU 2 – NUTS 2010, EU-28	Validated	2012
Correspondence table LAU 2 – NUTS 2010, EU-28 (Census)	Validated	2011
Correspondence table LAU 2 – NUTS 2010, EU-27	Validated	2011
Correspondence table LAU 2 – NUTS 2010, EU-27	Validated	2010