Update license and contact emails (#143)

Author: gowerc

DESCRIPTION

@@ -3,8 +3,8 @@ Type: Package
 Title: Dataframe Difference Tool
 Version: 1.1.1
 Authors@R: c( 
-    person("Craig" ,"Gower-Page" , email = "craig.gower-page@roche.com" , role = c("cre","aut")),
-    person("Kieran", "Martin" , email = "kieran.martin@roche.com" , role = "aut")
+    person("Craig" ,"Gower-Page" , email = "craiggower@gmail.com" , role = c("cre","aut")),
+    person("Kieran", "Martin" , email = "kieranjmartin@gmail.com" , role = "aut")
     )
 Description: Functions for comparing two data.frames against 
     each other. The core functionality is to provide a detailed breakdown of any differences 

LICENSE

@@ -1,2 +1,2 @@
-YEAR: 2018
-COPYRIGHT HOLDER: Craig Gower & Kieran Martin
+YEAR: 2025
+COPYRIGHT HOLDER: diffdf authors

LICENSE.md

@@ -0,0 +1,21 @@
+# MIT License
+
+Copyright (c) 2025 diffdf authors
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.