Changes in reference_counter.C for -Wshadow.

Issue #24.
Changes in nanoflann.hpp  for -Wshadow.

Issue #24.
Changes in type_vector.C for -Wshadow.

Issue #24.
Changes in quadrature_trap_2D.C for -Wshadow.

Issue #24.
Changes in quadrature_trap_3D.C for -Wshadow.

Issue #24.
Changes in adaptive_time_solver.C for -Wshadow.

Issue #24.
Changes in petsc_dm_nonlinear_solver.C for -Wshadow.

Issue #24.
Changes in petscdmlibmesh.C for -Wshadow.

Issue #24.
Changes in unsteady_solver.C for -Wshadow.

Issue #24.
Changes in continuation_system.C for -Wshadow.

Issue #24.
Changes in diff_context.C for -Wshadow.

Issue #24.
Changes in diff_system.C for -Wshadow.

Issue #24.
Changes in equation_systems.C for -Wshadow.

Issue #24.
Changes in explicit_system.C for -Wshadow.

Issue #24.
Changes in fem_context.C for -Wshadow.

Issue #24.
Changes in fem_system.C for -Wshadow.

Issue #24.
Changes in implicit_system.C for -Wshadow.

Issue #24.
Changes in linear_implicit_system.C for -Wshadow.

Issue #24.
Changes in newmark_system.C for -Wshadow.

Issue #24.
Changes in nonlinear_implicit_system.C for -Wshadow.

Issue #24.