[FIX] ODataModel: Don't create empty query string

In case an empty object or empty string was passed as urlParams or metadataUrlParam
instead of not defining it, we still added an unnecessary question mark to request URLs

Change-Id: Ibb78c353ecf07dfa4b6bd9f5ec34ea098a28a58f
BCP: 1482009883
Merge "[FIX] ODataModel: Don't create empty query string"
[INTERNAL] update grunt-openui5 dependency to 0.3.x

new version enables compression in "openui5_library_preload" task to
reduce preload file-size.

Change-Id: Ief3b5ec6f0c06a9a888d0f3d53f064650ac46393
Merge "[INTERNAL] update grunt-openui5 dependency to 0.3.x"