Defining a custom strtod on arm when using hard float breaks
since the function is marked in system headers as expecting a
soft abi. Hopefully strtod works on Android 5.0+ so the strtod
workaround is no longer needed.
Fixes#179.
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.
