Fix typos and strings

[rolandgeider]

• Trainer, can see the users for a gym, It should either be "Trainer: can see the users for a gym" or "a trainer can see the users for a gym". Same applies to entries bellow this one. This needs a DB upgrade since this is one of the custom permissions
• "Pending images" to "Images pending review" (or ingredients, exercises, etc.)
• "Reminder inactive members" sounds strange, this should either be "Reminder: inactive members" or "Reminder of inactive members"

[ywecur]

Should I add the items here instead of as comments on Transifex?

[rolandgeider]

Keep adding them in transifex, this issue is for things that can't be just fixed right away (e.g.because they are in the database, should be reviewed in context, etc.)

[rolandgeider]

BTW, I'll install your translation to the preview server, so you can check them in context, I'll let you know once I'm done.

[ywecur]

Alright, thanks!