Update README.md

Added 'pac-file' flag for PAC (Proxy Auto-Configuration) and Local Proxy details in local testing.

Author: thebeardedcoderIN

Diff for: README.md

@@ -78,6 +78,27 @@ To use a proxy for local testing -
 bs_local_args = { "key": "<browserstack-accesskey>", "proxyHost": "127.0.0.1", "proxyPort": "8000", "proxyUser": "user", "proxyPass": "password"}
 ```
 
+#### Local Proxy
+To use local proxy in local testing -
+
+* localProxyHost: Hostname/IP of proxy, remaining proxy options are ignored if this option is absent
+* localProxyPort: Port for the proxy, defaults to 8081 when -localProxyHost is used
+* localProxyUser: Username for connecting to proxy (Basic Auth Only)
+* localProxyPass: Password for USERNAME, will be ignored if USERNAME is empty or not specified
+
+```
+bs_local_args = { "key": "<browserstack-accesskey>", "localProxyHost": "127.0.0.1", "localProxyPort": "8000", "-localProxyUser": "user", "-localProxyPass": "password"}
+```
+
+#### PAC (Proxy Auto-Configuration)
+To use PAC (Proxy Auto-Configuration) in local testing -
+
+* pac-file: PAC (Proxy Auto-Configuration) file’s absolute path
+
+```
+bs_local_args = { "key": "<browserstack-accesskey>" , "-pac-file": "<pac_file_abs_path>"}
+```
+
 #### Local Identifier
 If doing simultaneous multiple local testing connections, set this uniquely for different processes - 
 ```sh