Re-number some image files related to kickers

[pixelzoom]

@amanda-phet and I discussed this. Some of the image files are not numbered to match the kicker that they correspond to.

For 'africa', see KickerPortrayalAfrica.

• [x] player05 => player11
• [x] player06 => player07
• [x] player07 => player13

For 'africaModest', see KickerPortrayalAfricaModest.

• [x] player01 => player03
• [x] player02 => player06
• [x] variabilityPlayer01 => variabilityPlayer02

I'll adjust these.

[pixelzoom]

This is done. @amanda-phet please review. Close if OK.

[amanda-phet]

Look good.