add viewer and merge changes
-rwxr-xr-x 983 CMakeLists.txt
-rwxr-xr-x 10753 LICENSE
drwxr-xr-x - account
drwxr-xr-x - block
drwxr-xr-x - common
drwxr-xr-x - composer
drwxr-xr-x - images
drwxr-xr-x - mailbox
drwxr-xr-x - main
drwxr-xr-x - packaging
drwxr-xr-x - po
drwxr-xr-x - setting
drwxr-xr-x - viewer