try to install dependencies automatically
fixed subshell issue
added after_failure
trying to fix: curl: (35) error:14077458:SSL routines:SSL23_GET_SERVER_HELLO:reason(1112)
try arm64 build on travis
try arm64 with FFmpeg 2.2
still trying FFmpeg 2.2 with arm64
FFmpeg 2.2.1
Merge branch '2.2.1'
updated README.md [skip ci]