Add util module to IfcOpenShell, including element, geolocation, unit, and selector. See #829.

src/ifcopenshell-python/ifcopenshell/util/geolocation.py

@@ -0,0 +1,24 @@
+def dms2dd(degrees, minutes, seconds, milliseconds=0):
+    dd = float(degrees) + float(minutes)/60 + float(seconds)/(3600)
+    return dd
+
+def dd2dms(dd):
+    dd = float(dd)
+    sign = 1 if dd >= 0 else -1
+    dd = abs(dd)
+    minutes, seconds = divmod(dd*3600, 60)
+    degrees, minutes = divmod(minutes, 60)
+    if dd < 0:
+        degrees = -degrees
+    return (int(degrees) * sign, int(minutes) * sign, int(seconds) * sign)
+
+def xyz2enh(x, y, z, eastings, northings, orthogonal_height, x_axis_abscissa, x_axis_ordinate, scale=None):
+    if scale is None:
+        scale = 1.
+    rotation = atan2(x_axis_ordinate, x_axis_abscissa)
+    a = scale * cos(rotation)
+    b = scale * sin(rotation)
+    eastings = (a * x) - (b * y) + eastings
+    northings = (b * x) + (a * y) + northings
+    height = z + orthogonal_height
+    return (eastings, northings, height)