this is done by removing zlib/bz2 explicit dependencies because they are unnecessary
we only ever use the stream filter, and the check for existence has
been moved to runtime where it is after startup
Phar is enabled as a shared extension by default in order to allow zlib/bz2 to be built shared. If phar is statically built,
both zlib and bz2 must be statically built in order for phar to use them, so default compile as shared is much more flexible
