Addition of ProgressMeter using ProgressMeter.jl

[amitjamadagni]

Adding the macros :

@showprogress, @showprogress_trace, @showprogress_expectation which return the evolved states, trace of the evolved states, expectation values with respect to expectation operators. The first two accept QuPropagator as parameter, while the last requires the expectation operators.

But this does not work :

julia> qpro = QuPropagator(sigmax+2*sigmay+3*sigmaz, [lowerop(2)*sqrt(3), raiseop(2)*sqrt(2)], statevec(1, FiniteBasis(2))*statevec(1, FiniteBasis(2))', 0.:0.1:24000, QuExpmV())

julia> @showprogress qpro
ERROR: UndefVarError: qpro not defined

[coveralls]

Coverage increased (+0.2%) to 90.157% when pulling cf51ec9 on amitjamadagni:progress_meter into 663ed56 on JuliaQuantum:master.

[coveralls]

Coverage remained the same at 89.916% when pulling cf51ec9 on amitjamadagni:progress_meter into 663ed56 on JuliaQuantum:master.

[coveralls]

Coverage increased (+6.3%) to 89.916% when pulling d590f96 on amitjamadagni:progress_meter into 2f90739 on JuliaQuantum:master.

[coveralls]

Coverage remained the same at 83.594% when pulling a3db4d6 on amitjamadagni:progress_meter into 2f90739 on JuliaQuantum:master.