Added a gitignore file for the Finale music notation software

Finale.gitignore

@@ -0,0 +1,14 @@
+*.bak
+*.db
+*.avi
+*.pdf
+*.ps
+*.mid
+*.midi
+*.mp3
+*.aif
+*.wav
+# Some versions of Finale have a bug and randomly save extra copies of
+# the music source as "<Filename> copy.mus"
+*copy.mus
+