Made two compile options dependent on whether or not the plugins are
selected.
Removed autoreconf as autools files are not being patched.
Added PKG_BUILD_PARALLEL for faster compilation.
Added patch to fix compilation with libjpeg-turbo. libjpeg-turbo can be
fixed to include this API, but it's probably better for size reasons to
patch libextractor instead.
Added -liconv since it seems to be needed for some reason.
Signed-off-by: Rosen Penev <rosenp@gmail.com>
