Add documentation to resolve the "Header Fields are too long" issue (#4)

Setting CONFIG_HTTPD_MAX_URI_LEN=1024 in your project's sdkconfig.defaults file will ensure the captive portal works on more devices, like Android.

Also applied the setting as under the examples.

Fixes tonyp7#147

Authored-by: Adam McDaniel <[email protected]>

Author: MagicSmokeSolutions

README.md

@@ -123,6 +123,12 @@ EXTRA_COMPONENT_DIRS := components/
 include $(IDF_PATH)/make/project.mk
 ```
 
+Update your `sdkconfig.defaults` to allow for larger HTTP Request URL lengths.  This is required by some operating systems in order to use its captive portal UI to configure wifi.
+
+```config
+CONFIG_HTTPD_MAX_URI_LEN=1024
+```
+
 Once this is done, you can now in your user code add the header:
 
 ```c

examples/default_demo/sdkconfig.defaults

@@ -1 +1,2 @@
 CONFIG_LWIP_IPV6=y
+CONFIG_HTTPD_MAX_URI_LEN=1024

examples/http_hook/sdkconfig.defaults

@@ -1 +1,2 @@
 CONFIG_LWIP_IPV6=y
+CONFIG_HTTPD_MAX_URI_LEN=1024