ERT-565: Change after review: Check if util_sscanf_int succeeds
ERT-565: Change after review: Method util_sscanf_percent: Using strtod method for a better implementation of this method. Also removed /100 to users of the function. That is, scannong 10% returns number 10
ERT-565: Changes after review: Only accept percent tokens with no space between the number and the %