Create store directory paths in CSM constructor for disk space monitor

[shekhars-li]

Fix for the bug: https://issues.apache.org/jira/browse/SAMZA-2752

What: Set durable store names in a set in the ContainerStorageManager constructor

Why: During previous refractoring, the createStore for durable stores was moved outside of constructor. However, the store directory paths are required to be set in constructor so that SamzaContainer class can set monitors for them. This patch sets the store names without creating the stores, so that monitoring can be set properly.