Added MSVC output directories to gitignore.

.gitignore

@@ -34,4 +34,19 @@ celt/dump_modes/dump_modes
 *.vcxproj.user
 opus.sdf
 opus.suo
-version.h
\ No newline at end of file
+version.h
+celt/Debug
+celt/Release
+celt/x64
+silk/Debug
+silk/Release
+silk/x64
+silk/fixed/Debug
+silk/fixed/Release
+silk/fixed/x64
+silk/float/Debug
+silk/float/Release
+silk/float/x64
+src/Debug
+src/Release
+src/x64
\ No newline at end of file