Added "immutable" option to LocalStorage handlers. This is to get
configuration variables out of the session. Stuff like "lane number"
or "SQL host" never changes so there's no reason to pass it around
in session. Always including ini.php provides the same definitions.
Scripts that only need this information and not REAL session values
(i.e., values that change as POS runs) can run completely in the
background.
BUGFIX: Install pages need to use immutable arg in set() calls
Fix for strict class method warnings and class redeclaration error
Merge pull request #124 from CORE-POS/extra-config-bugfix

FYI: Fix for strict class method warnings and class redeclaration error
FIX: else should be elseif
Merge branch 'master' of https://github.com/CORE-POS/IS4C
Merge branch 'akt-immutable-settings' of https://github.com/CORE-POS/IS4C

Conflicts:
	pos/is4c-nf/install/extra_config.php