Merge pull request #26 from gsar/master

avoid loose matching on msoffice formats in overlay.rb

lib/mimemagic/overlay.rb

 # Extra magic
 # Extra magic
 
 
-[['application/vnd.openxmlformats-officedocument.presentationml.presentation', [[0..5000, 'ppt/']]],
- ['application/vnd.openxmlformats-officedocument.spreadsheetml.sheet', [[0..5000, 'xl/']]],
- ['application/vnd.openxmlformats-officedocument.wordprocessingml.document', [[0..5000, 'word/']]]].each do |magic|
+[['application/vnd.openxmlformats-officedocument.presentationml.presentation', [[0, "PK\003\004", [[30, '[Content_Types].xml', [[0..5000, 'ppt/']]]]]]],
+ ['application/vnd.openxmlformats-officedocument.spreadsheetml.sheet', [[0, "PK\003\004", [[30, '[Content_Types].xml', [[0..5000, 'xl/']]]]]]],
+ ['application/vnd.openxmlformats-officedocument.wordprocessingml.document', [[0, "PK\003\004", [[30, '[Content_Types].xml', [[0..5000, 'word/']]]]]]]].each do |magic|
   MimeMagic.add(magic[0], magic: magic[1])
   MimeMagic.add(magic[0], magic: magic[1])
 end
 end