Low-level declarers optimized.

Low-level declarers (e.g., ::declare_func_stop()) internally performed an excess
of eval() statements, purportedly harming startup efficiency in a non-negligible
manner. All such statements have been refactored into non-eval() equivalents,
with concomitant improvements in efficiency.

Also corrected minor Portage-specific regressions.

In short: yay.