This fixes Android 6 problems (so closes#26).
It also rebuilds termux-elf-cleaner when needed
and bumps some build revisions for packages
needed updates to remove DT_VERDEF and DT_VERDEFNUM.
Move the CA certs from libcurl to separate ca-certificates package which both openssl and gnutls depends on.
For a smooth upgrade without packages clashing with the same file, rename etc/ssl to etc/tls.
Also update gnutls to latest version and give configure argument to use common certificate file.
