Upgrade packages to Julia 0.7

[dpo]

The first step should be for all packages to support 0.6 and 0.7. A second step will remove 0.6 support.

The goal is not to remove all deprecation warnings. We can live with warnings about Pkg or LinearAlgebra for a while until 0.6 support is removed.

The packages should be more or less in topological order.

• AMD (Update 0.7 AMD.jl#14)

• LDLFactorization (julia 0.7 + deprecation warnings LDLFactorizations.jl#5)

• LimitedLDLFactorization (updates for julia 0.7 LimitedLDLFactorizations.jl#3)

• BenchmarkProfiles (updates for julia 0.7 BenchmarkProfiles.jl#19)

• LinearOperators (Update to 0.7 - don't drop 0.6 LinearOperators.jl#57)

• PROPACK (Julia 0.7 PROPACK.jl#13)

• Krylov (Add 1.0 to travis and appveyor Krylov.jl#59)

• MUMPS (Julia 0.7 initial MUMPS.jl#30)

• HSL

• NLPModels

• OptimizationProblems

• NLSProblems

• CUTEst

• AmplNLReader

• Optimize