#5 Add citation file (without DOI)

Author: astropenguin

CITATION.cff

@@ -0,0 +1,14 @@
+cff-version: 1.2.0
+message: "If you use this software, please cite it as below."
+
+title: "deshima-rawdata"
+abstract: "DESHIMA raw data and downloader package"
+version: 2023.11.0
+date-released: 2023-11-10
+license: "MIT"
+url: "https://github.com/deshima-dev/rawdata"
+authors:
+  - given-names: "Akio"
+    family-names: "Taniguchi"
+    affiliation: "Nagoya University"
+    orcid: "https://orcid.org/0000-0002-9695-6183"