add source.type field

forc-db/IPCC-EFDB-integration#22

@mawilliams99 , could you please add this to citations table as well?

Author: teixeirak

database_management_records/record_of_changes.csv

@@ -10,5 +10,6 @@ Citations,citation.citation,Full citation. Most of these records are automatical
 ,citation.language,"Language of original publication, automatically generated based on the title and abstract, with some manual entries and corrections.",field added,field required by IPCC,2021-Mar
 ,citation.url,"URL of original publication, generally retrieved automatically via URL lookup.",field added,field required by IPCC,2021-Mar
 ,citation.abstract,"Abstract, generally retrieved automatically via DOI lookup.",field added,field required by IPCC,2021-Mar
+,source.type,citation source type,field added,field required by IPCC,2021-Jun
 ,pdf.in.repository,Indicates whether pdf of original study has been retrieved and saved in ForC's reference repository,field added,housekeeping,2021-Mar
 ,EFDB.ready,Indicates whether data have been checked for export to EFDB.,field added,housekeeping,2021-Jun

metadata/citations_metadata.csv

@@ -8,5 +8,6 @@ Column,Field,Description,Storage.Type,Variable.Codes,n,Min,Max
 7 / G,citation.language,"Language of original publication. This was generated based on the title and abstract (retrieved via DOI lookup), and may mis-identify some that have title and abstract in English, but main article in another language.",character (string),-,,,
 8 / H,citation.url,URL of original publication.,character (string),-,,,
 9 / I,citation.abstract,"Abstract, generally retrieved automatically via DOI lookup.",character (string),-,,,
-10 / J,pdf.in.repository,Indicates whether pdf of original study has been retrieved and saved in ForC's reference repository: https://github.com/forc-db/References (private repository; contact database managers for access).,numeric (integer),1- true; 0 -false,,,
-11 / K,EFDB.ready,Indicates whether data have been checked for export to EFDB.,numeric (integer),1- true; 0 -false,,,
+10 / J,source.type,type of data source,character (string),"peer-reviewed journal, thesis, book, personal communication, other",,,
+11 / K,pdf.in.repository,Indicates whether pdf of original study has been retrieved and saved in ForC's reference repository: https://github.com/forc-db/References (private repository; contact database managers for access).,numeric (integer),1- true; 0 -false,,,
+12 / L,EFDB.ready,Indicates whether data have been checked for export to EFDB.,numeric (integer),1- true; 0 -false,,,