Modify ConnectionManager to non-static

Modify ConnectionManager to non-static

Static class ConnectionManager cannot be created multiple time.
It causes a problem in multi-thread environment.
Handle created in one thread cannot be used in other threads due to characteristics of handle-based native connection capi.
Therefore ConnectionManager is modified to map one ConnectionManager
instance to one native capi handle.

Change-Id: If1e80df24400bc6477717f33eaadb05a198c3322
Signed-off-by: cheoleun <chleun.moon@samsung.com>