Adds import support for fitting window copy. Resolves #91

This requires us to pass an active fit to use as a base for the modules, as the format does not include ship information. Features:
* If active fit has modules, makes a new fit using same ship
* Does basic dummy checking. As the format doesn't include ship info, it will probably be common for someone to accidentally try to import a Legion fit to a Rifter by mistake. Import logic checks module legality for fit and, if fails, silently halts import without saving.

service/fit.py

@@ -744,8 +744,8 @@ class Fit(object):
             fit.damagePattern = self.pattern
         return fits
 
-    def importFitFromBuffer(self, buffer):
-        type,fits = eos.types.Fit.importAuto(buffer)
+    def importFitFromBuffer(self, buffer, activeFit=None):
+        type,fits = eos.types.Fit.importAuto(buffer, activeFit=activeFit)
         for fit in fits:
             fit.character = self.character
             fit.damagePattern = self.pattern