LMS class constructor modification

Changes old style constructor to new one.
LMS class members as public properties

Changes deprecated 'var' LMS class members into 'public' properties.
LMS class methods as public methods

Changes visibility of LMS class methods to public.
LMSDB_common class constructor modification

Changes old style constructor to new one.
LMSDB_common class members as public properties
LMSDB_common class methods as public methods
LMSDB_driver_mysql class new constructor, properties and methods visibility
LMSDB_driver_mysqli class new constructor, properties and methods visibility
LMSDB_driver_postgres class new constructor, properties and methods visibility
Auth class new constructor, properties and methods visibility
ExecStac class new constructor, properties and methods visibility
Session class new constructor, properties and methods visibility
Sysinfo class new constructor, properties and methods visibility
Merge pull request #222 from maciejlew/oop

Constructors, properties and methods visibility in new PHP5 style for some LMS base classes