Add .editorconfig file to override IDE defaults

Add rules for enforcing tabs in Java, and spaces in Ruby.

Add a rule to make sure trailing whitespace is trimmed
and that no new final newline is inserted.

.editorconfig

@@ -0,0 +1,13 @@
+root = true
+
+[*]
+trim_trailing_whitespace = true
+insert_final_newline = false
+
+[*.java]
+indent_style=tab
+tab_width=4
+
+[*.rb]
+indent_style=space
+indent_size=2

.gitignore

@@ -1,7 +1,9 @@
+.*
+
 !.gitignore
 !.rubocop.yml
+!.editorconfig
 
-.*
 *~
 *.class
 *.iml
@@ -10,3 +12,4 @@
 /data/savedGames
 /lib/
 */target/
+