don't display objects without ports in gvmap
don't display backend links without front connection on "Showing all objects" gv map
rename const MULTILINK -> LM_MULTILINK use define() for compat with php < 5.3
fix backend link display without front link
change graph generation change highlight handling
fix error_reporting in linkmgmt_gvmap
fix undef. property $alpha
add lm_Image_GraphViz
rearrange code
fix Undefined variable
optimize All Objects Graph