Added functionality to create custom OpenCL functions from user provided kernels

Added 'synchronize' function to assure completion of device calls (necessary for benchmarking)

Added determinant function (det)

Allow for gpuR object - base object interaction (e.g. vclMatrix * matrix)

Added ‘inplace' function for ’inplace' operations. These operations include '+', '-', '*', '/', 'sin', 'asin', 'sinh', 'cos', 'acos', 'cosh', 'tan', 'atan', 'tanh'.

Added 'sqrt', 'sum', 'sign','pmin', and 'pmax' functions

Methods to pass two gpuR matrix objects to 'cov'

Added 'norm' method

Added gpuRmatrix/gpuRvector Arith '+','-' methods