Small improvements in documentation here and there.

Author: Manciukic

bluetooth/src/main/java/org/cloudbus/foggatewaylib/bluetooth/BluetoothLeNotifyProvider.java

@@ -52,6 +52,8 @@ public void execute(long requestID, VoidData... input) {
 
     /**
      * Called when the characteristic value changes, provides the output to be published.
+     * You can retrieve the value of the characteristic from within the method through
+     * {@link BluetoothGattCharacteristic#getValue()} (or equivalent).
      *
      * @param gatt the GATT server in which the change occurred.
      * @param characteristic the updated characteristic.

bluetooth/src/main/java/org/cloudbus/foggatewaylib/bluetooth/BluetoothLeReadProvider.java

@@ -53,6 +53,8 @@ public void execute(long requestID, VoidData... input) {
 
     /**
      * Called when the characteristic value is read, provides the output to be published.
+     * You can retrieve the value of the characteristic from within the method through
+     * {@link BluetoothGattCharacteristic#getValue()} (or equivalent).
      *
      * @param gatt the GATT server in which the read occurred.
      * @param characteristic the read characteristic.

core-java/src/main/java/org/cloudbus/foggatewaylib/core/ExecutionManager.java

@@ -14,6 +14,9 @@
  * Orchestrator and manager of the other components ({@link Store}, {@link Provider},
  * {@link Chooser}, {@link Trigger}).
  *
+ * In order to be used, each component should be registered withing the {@link ExecutionManager}
+ * using one of the {@code add*} methods.
+ *
  * @see Store
  * @see Provider
  * @see Chooser