src/webapp/base-framework.php: If redirect is performed for non-GET/non-HEAD HTTP request (for path normalization purpsoses), issue warning instead of raising exception.
src/webapp/base-framework.php: Add hook to issue warning if the default value for 'session.gc_maxlifetime' is less than the webapp's configured session lifetime; this because on some systems (e.g., Ubuntu) setting the 'session.gc_maxlifetime' value at runtime may not cut it.