phar enabled by default as of now

Hi, I just committed to ext/phar's config.m4/w32 to make phar enabled by default as a shared extension. This is a better default setting than building phar in statically, as phar has optional dependencies on the zlib and bz2 extensions to enable compressed phar archives. If phar is built statically, then it would require both zlib and bz2 to be built statically in order to use them, something that is obviously not going to happen, as they have been around a while and nobody has even suggested it (to my knowledge). Having phar shared means one can easily plug in zlib/bz2 support without recompiling PHP. I'm open to further input/tweaks on this decision. If you have a better idea, go ahead and commit to phar's config.m4/w32, these files are very easy to change if needed. Greg