add support for VIVA .trc file export

[mattmilten]

Add a method that can output a TRC file to be read by VIVA.

example TRC file:

alan,MINLP,scip,CONOPT,CPLEX,43358.445,0,8,9,4,24,3,1,8,1,2.92500006672242,2.92211381078608,0.137,165,0,1,#
ball_mk2_10,MINLP,scip,CONOPT,CPLEX,43358.445,0,2,11,10,21,10,1,1,1,0,0,0.002,0,0,1,#

meaning of the values:

InputFileName
ModelType
SolverName
NLP
MIP
JulianDate
Direction
NumberOfEquations
NumberOfVariables
NumberOfDiscreteVariables
NumberOfNonZeros
NumberOfNonlinearNonZeros
OptionFile
ModelStatus
TermStatus
ObjectiveValue
ObjectiveValueEstimate
SolverTime
NumberOfIterations
NumberOfDomainViolations
NumberOfNodes
UserComment