Changed compileWhereIn function

MongoDB 2.6.0, no longer accepting bson object in the $in clause. To fix this, the values need to be numerically indexed starting from zero and have consecutive values.

Adding array_values fixed this issue.

This fix was not tested on a previous MongoDB version.

Fix #325

Fix for #321 Problem after Laravel upgrade 4.2.8 to 4.2.9

New v2 release