Better GRASS detection on Windows, fixed GRASS engine reference bug

app/plugins/grass_engine.py

@@ -12,11 +12,17 @@ logger = logging.getLogger('app.logger')
 class GrassEngine:
     def __init__(self):
         self.grass_binary = shutil.which('grass7') or \
+                            shutil.which('grass7.bat') or \
                             shutil.which('grass72') or \
+                            shutil.which('grass72.bat') or \
                             shutil.which('grass74') or \
+                            shutil.which('grass74.bat') or \
                             shutil.which('grass76') or \
+                            shutil.which('grass76.bat') or \
                             shutil.which('grass78') or \
-                            shutil.which('grass80')
+                            shutil.which('grass78.bat') or \
+                            shutil.which('grass80') or \
+                            shutil.which('grass80.bat')
 
         if self.grass_binary is None:
             logger.warning("Could not find a GRASS 7 executable. GRASS scripts will not work.")
@@ -34,7 +40,7 @@ class GrassContext:
         if tmpdir is None:
             tmpdir = os.path.basename(tempfile.mkdtemp('_grass_engine', dir=settings.MEDIA_TMP))
         self.tmpdir = tmpdir
-        self.script_opts = script_opts
+        self.script_opts = script_opts.copy()
         self.location = location
         self.auto_cleanup = auto_cleanup
 
@@ -95,7 +101,7 @@ class GrassContext:
             try:
                 out = subprocess.check_output(command, cwd=self.get_cwd()).decode('utf-8').strip()
                 success = True
-            except subprocess.CalledProcessError:
+            except:
                 success = False
                 err = out
         else: