Android UCI engine update: Corchess 1.7.20170726.ACH

It's interesting to see a 1.7 version dated 26th while there was a 1.8 version dated 20th, previously posted here. The most recent should be better by theory anyway.

GET Corchess 1.7.20170726 for arm7 and arm8.

In case of trouble downloading from your PC, use your mobile device or refer to THIS POST.