Preparing for removing ServiceStack

Signed-off-by: Seemant Rajvanshi <seemant.rajvanshi@gmail.com>
Removed dependency on FlexSearch.API dll

Signed-off-by: Seemant Rajvanshi <seemant.rajvanshi@gmail.com>
ServiceStack is removed completely
Keyvalue store implementation complete

Signed-off-by: Seemant Rajvanshi <seemant.rajvanshi@gmail.com>