Revert "use CADisplayLink instead of NSTimer"
Revert "use CADisplayLink instead of NSTimer"

This reverts commit baef558b8a0377a82a3edacab22a1f4ea1a2c3e4.

criticalmaps/criticalmaps-ios,headione/criticalmaps-ios,criticalmaps/criticalmaps-ios,criticalmaps/criticalmaps-ios