Improve the platformio support

Author: MaJerle

CHANGELOG.md

@@ -3,6 +3,7 @@
 ## Develop
 
 - Rework library CMake with removed INTERFACE type
+- Fix the platformio library package description
 
 ## 1.2.0
 

library.json

@@ -33,6 +33,8 @@
 		]
 	},
     "build": {
-        "includeDir": "lwshell/src/include"
+        "includeDir": "lwshell/src/include",
+        "srcDir": ".",
+        "srcFilter": "+<lwshell>"
     }
 }