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"
Merge pull request #394 from jamaa/module_info_imagesize

Add an option to the info module to display the image size (in pixels) of the current item.

Fixes #2075
Automated update of .build_number to 301 for branch 3.0.x
Last update: 16a88d34aedbdde121a0c93cefffcb36cbc9aea0 (1 commits ago)
[ci skip]
Style cleanup.
Automated update of .build_number to 302 for branch 3.0.x
Last update: 2c764b0c2b96fb56c6402bea823d8672341cc047 (1 commits ago)
[ci skip]