update libgcrypt to get latest ARM/NEON optimization fixes
build libgcrypt with auto-detection of NEON

Revert "disable all assembly in libgcrypt until it is fully functional"

This reverts commit 21806d462344b2343e9d526896eee76f2d4e2d62.

refs #2807
tests: include importing secret keys as part of standard tests

refs #1270
tests: cat GnuPG debug logs from emulator

This outputs more debug info to the Jenkins build.

refs #1270
disable failing tests: libassuan/fdpassing libgcrypt/random-fips-rng

* libassuan/fdpassing - this should pass on Android, but needs to be rewritten
  in C rather than a shell script

* libgcrypt/random --prefer-fips-rng - this should pass on Android, but it is
  not high priority and no one has had time to debug it yet

refs #1270