pauseAllRequests
Cancels any in progress loads and clears resources of completed loads.
Note #resumeRequests must be called for any requests made before or while the manager is paused to complete. RequestManagers attached to Fragments and Activities automatically resume onStart().
This will release the memory used by completed bitmaps but leaves them in any configured caches. When an #android.app.Activity receives #onTrimMemory at a level of #TRIM_MEMORY_BACKGROUND this is desirable in order to keep your process alive longer.