Added file header

NanoVNASaver/SITools.py

@@ -1,3 +1,19 @@
+#  NanoVNASaver
+#  A python program to view and export Touchstone data from a NanoVNA
+#  Copyright (C) 2019.  Rune B. Broberg
+#
+#  This program is free software: you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation, either version 3 of the License, or
+#  (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with this program.  If not, see <https://www.gnu.org/licenses/>.
 import math
 from numbers import Number
 
@@ -73,7 +89,6 @@ class Value(object):
 
         return result + fmt.space_str + PREFIXES[offset + 8] + self._unit
 
-
     def parse(self, value: str):
         value = value.replace(" ", "")  # Ignore spaces
         if self._unit and value.endswith(self._unit):  # strip unit