Fixes to assertions and overrides

[nkoukpaizan]

Description

Building in debug mode revealed a few asserts that were failing

One failing assertion was due to a member function name change:

GridKit/src/Solver/Optimization/DynamicConstraint.cpp:31:22: error: no member named 'size_quad' in 'GridKit::Model::Evaluator<double, long>'
   31 |       assert(model_->size_quad() == 1);
      |              ~~~~~~  ^

Another failing assertion was due to a comparison between two floating point numbers:

Assertion failed: (t == other.t), function operator-=, file example2.cpp, line 42.

Additionally, LLVM tends to issue more warnings, such as overrides

GridKit/tests/UnitTests/Solver/Dynamic/IdaTests.hpp:113:29: warning: 'y' overrides a member function but is not marked 'override' [-Winconsistent-missing-override]
  113 |       std::vector<ScalarT>& y()
      |

Proposed changes

• size_quad() --> sizeQuadrature()
• Use a tolerance to compare the floating point values in example2. Also put the data within a namespace.
• Adding missing overrides

Checklist

• All tests pass.
• Code compiles cleanly with flags -Wall -Wpedantic -Wconversion -Wextra.
• The new code follows GridKit™ style guidelines.
• There are unit tests for the new code.
• The new code is documented.
• The feature branch is rebased with respect to the target branch.

Further comments

I suggest ignoring whitespaces for the diff for the example*hpp files.

[pelesh]

Tests pass when built with GCC and Clang. Good to merge.

[pelesh]

I suggest using GridKit's comparison for floating point numbers:

#include <Utilities/Testing.hpp>

...

assert(isEqual(t, other.t));