Material: cards, remove spcific price values

src/Mod/Material/StandardMaterial/ABS.FCMat

@@ -8,7 +8,6 @@ Name = ABS
 Description = This is a blend AcrylnitrilButadienStyrol (ABS) material card. The values are at the low end of the spectrum. If you need a more precise material definition use the more specialised ABS-blend cards.
 Father = Thermoplast
 ProductURL = http://en.wikipedia.org/wiki/Acrylonitrile_butadiene_styrene
-SpecificPrice = 3
 YoungsModulus = 2320 MPa
 UltimateTensileStrength = 38 MPa
 PoissonRatio = 0.35

src/Mod/Material/StandardMaterial/None.FCMat

@@ -7,7 +7,6 @@
 Name = None
 Description = This is a not defined material
 Father = None
-SpecificPrice = 0
 YoungsModulus = 0 MPa
 UltimateTensileStrength = 0 MPa
 PoissonRatio = 0

src/Mod/Material/StandardMaterial/PLA.FCMat

@@ -8,7 +8,6 @@ Name = PLA
 Description = Polylactic acid or polylactide (PLA, Poly) is a biodegradable thermoplastic aliphatic polyester derived from renewable resources, such as corn starch, tapioca roots, chips, starch or sugarcane.
 Father = Thermoplast
 ProductURL = http://en.wikipedia.org/wiki/Polylactic_acid
-SpecificPrice = 4
 YoungsModulus = 3640 MPa
 UltimateTensileStrength = 49.6 MPa
 PoissonRatio = 0.36

src/Mod/Material/StandardMaterial/Steel-Generic.FCMat

@@ -8,7 +8,6 @@ Name = Steel-Generic
 Description = This is a blend Steel material card. The values are at the low end of the spectrum. If you need a more precise material definition use the more specialised steel cards.
 Father = Metal
 ProductURL = http://en.wikipedia.org/wiki/Steel
-SpecificPrice = 1.5 Euro/kg
 YoungsModulus = 200000 MPa
 PoissonRatio = 0.3
 Density = 7900 kg/m^3