Gallery2: refactor strings

Change-Id: I95a78d2f5902f8603804758b114a0a1f8942e608
Gallary2: Japanese translation

PS2: also modify picture size entry

Change-Id: I52bc3c10e93dc3a5d52cf792060a36af65bd8377
Merge "Gallery2: refactor strings" into cm-10.2
Merge remote-tracking branch 'cm/cm-10.2' into DJL10.2