Add JPEG image support

Packages describing “jpeg” as local USE flag

Package“jpeg” Flag Description
app-emulation/qemuEnable jpeg image support for the VNC console server
gui-apps/grimEnable JPEG support.
gui-libs/neatvncEnable JPEG compression
media-libs/imlib2Jpeg image loader support
sci-electronics/pcbJPEG graphics export
x11-wm/ctwmEnable jpeg image support with virtual/jpeg

All packages providing a “jpeg” USE flag (100)