Update of classpath file and libs/libs-source

This commit updates the classpath file to include the class path entry
of the external libraries required to operate Google Calendar and
Google Tasks API.

It also adds in the external .JAR libraries in the “libs” folder.

The “libs-source” folder contains the “___-sources.jar” of the
corresponding external library.

The “libs-source/javadoc” folder contains the corresponding javadoc.jar
files where applicable.

The “resources” folder contains a file called “client_secrets.json”
which contains our application’s OAuth 2.0 credentials to let our app
authenticate to the correct Google Developer Project “ChirpTask”.
Include javadoc reference in classpath

This commit includes the javadoc reference for Google Calendar and
Google Tasks in the classpath file.