publish libraries to avoid users to have to download them one by one

lib/WiFiManager/library.properties

@@ -0,0 +1,9 @@
+name=WiFiManager
+version=0.12
+author=tzapu
+maintainer=tzapu
+sentence=ESP8266 WiFi Connection manager with fallback web configuration portal
+paragraph=Library for configuring ESP8266 modules WiFi credentials at runtime.
+category=Communication
+url=https://github.com/tzapu/WiFiManager.git
+architectures=esp8266