Remove constexpr square root call in CDI

[alexrlongne]

Background

• I used constexpr square root in a Require function to make sure overflow would not result when an input value was squared. I thought this was a good idea because the sqrt(std::numeric_limits<double>::max) was previously being computed every time through this loop. Unfortunately, it seems that debug code versions were not evaluating this expression at compile time and it was causing very slow runtimes and even more problems under profiling (the ce_sqrt is not an efficient version of sqrt it's just one that can be marked constexpr!). This PR removes the ce_sqrt call and replaces it with the sqrt of the max double. There is a comment explaining the magic number.

Purpose of Pull Request

• Fix slow runtimes and profiling times in debug mode

Description of changes

• Replace constexpr squar root call with a numeric value

Status

• Reference:
  • Pre-Merge Code Review
  • CDash Status
• Checks
  • Travis/Appveyor CI checks pass
  • Code coverage does not decrease
  • Valgrind test passes
  • Toss3 checks pass
  • Trinitite checks pass
  • Code reviewed/approved, sufficient DbC checks, testing, documentation

[KineticTheory]

Something seems wrong with the history of this branch. The diff shows a bunch of files from kde as modified. Can you rebase and/or squash?

[alexrlongne]

@KineticTheory Sorry about that, it should be fixed now.