Remove unused code and classes.
Clean up code to remove all named constant from them and throw
deprecation alerts if used.
Add basic psalm setup in root folder and remove from www folder
Convert\VarSetType for always return type expected (eg string will be string)
or Convert\VarSetTypeNull to return string or null on failure
The return value for failure if not matching type can be set for both, but
only for Convert\VarSetTypeNull the return value can be set to null.
DB\IO dbReturn method has a third parameter to set read only assoc and
not number data from the query
Install basic composer for trying out psalm
setting phpan/phpstan for basic static checking and do basic clean up on
all of the files
