add the image size (in pixels) to the info module

adds a new variable "show_size", so had to increment the version number
to 3
fix whitespace
fix upgrade function

allow for sequential upgrades
internationalize image size display

as per comment
https://github.com/gallery/gallery3/pull/394/files#r4643737
change "size" to "dimensions" and display unit "px"
Automated update of .build_number to 422 for branch master
Last update: 47803a2d46df8f567639ba7f6d2afb63655afc19 (5 commits ago)
[ci skip]