Fix for switch to user not bring up switching screen + Misc changes (most already in unstable23)

Fix for switch to user not bringing up switching screen: the fix is actually in shared and was commited straight to forcedotcom/SalesforceMobileSDK-Shared (I was working from submodule thinking it was pointing to wmathurin/SalesforceMobileSDK-Shared), any way the commit is here: https://github.com/forcedotcom/SalesforceMobileSDK-Shared/commit/0987de7163a497d02bbfccf95594fa4d6ac9c77a

Other fixes:
- distinct account_type for each app
- removed unused test projects for ContactExplorer/SmartStoreExplorer and VFConnector (they were very unstable and therefore never run)
- sfaccountmanager plugin was not in all config.xml