use WTTR_IP2LOCATION_KEY_FILE ot override ip2location key location

lib/globals.py

@@ -83,7 +83,9 @@ PLAIN_TEXT_AGENTS = [
 
 PLAIN_TEXT_PAGES = [':help', ':bash.function', ':translation', ':iterm2']
 
-_IP2LOCATION_KEY_FILE = os.environ['HOME'] + '/.ip2location.key'
+_IP2LOCATION_KEY_FILE = os.environ.get(
+    "WTTR_IP2LOCATION_KEY_FILE",
+    os.environ['HOME'] + '/.ip2location.key')
 IP2LOCATION_KEY = None
 if os.path.exists(_IP2LOCATION_KEY_FILE):
     IP2LOCATION_KEY = open(_IP2LOCATION_KEY_FILE, 'r').read().strip()