pcb/layers.txt.tmpl

   1 back            back    gbr     Back (solder-side) copper
   2 backmask        backmask gbr    Back (solder-side) solder resist
   3 fab             fab     gbr     Fabrication diagram
   4 front           frnt    gbr     Front (component-side) copper
   5 frontmask       frntmask gbr    Front (component-side) solder resist
   6 frontsilk       frntsilk gbr    Front (component-side) silk screen
   7 plated-drill    drill   cnc     NC drill (plated; finished sizes specified)