Add a GitHub issue template
Add a GitHub issue template

This should save our customers a roundtrip when filing for bugs/issues.

aws/aws-sdk-cpp,JoyIfBam5/aws-sdk-cpp,JoyIfBam5/aws-sdk-cpp,aws/aws-sdk-cpp,awslabs/aws-sdk-cpp,JoyIfBam5/aws-sdk-cpp,aws/aws-sdk-cpp,JoyIfBam5/aws-sdk-cpp,aws/aws-sdk-cpp,awslabs/aws-sdk-cpp,cedral/aws-sdk-cpp,aws/aws-sdk-cpp,jt70471/aws-sdk-cpp,cedral/aws-sdk-cpp,cedral/aws-sdk-cpp,jt70471/aws-sdk-cpp,cedral/aws-sdk-cpp,jt70471/aws-sdk-cpp,JoyIfBam5/aws-sdk-cpp,cedral/aws-sdk-cpp,JoyIfBam5/aws-sdk-cpp,awslabs/aws-sdk-cpp,awslabs/aws-sdk-cpp,jt70471/aws-sdk-cpp,jt70471/aws-sdk-cpp,aws/aws-sdk-cpp,jt70471/aws-sdk-cpp,cedral/aws-sdk-cpp