change default location for solver output

Author: thowell

src/solver.jl

@@ -17,7 +17,7 @@
     diverging_iterates_tol::T = 1.0e8
     mu_target::T = 1.0e-4
     print_level::Int = 5
-    output_file = joinpath(dirname(pathof(DirectTrajectoryOptimization)), "..", "output.txt")
+    output_file = "output.txt"
     print_user_options = "no"
     # print_options_documentation = "no"
     # print_timing_statistics = "no"