[PUSHED] adding calc add-in for option pricing

[tino]

> >Do you mean function names like getOpt_barrier() or input variables as
> >put_call or both? If it's the function names then would
> >getOpt_barrier() --> getOptBarrier() be ok?
> 
> Ah, right, some parameter names are affected, too.  So yes, please
> replace all identifiers containing underscores with "camel-case"
> identifiers (where whether the latter are more or less beautiful
> than the former is an entirely unrelated topic... :)

Just to be clear, are we only talking about XPricingFunctions.idl as
far as the variable names are concerned? Obviously, for the function
names I have to change them in a few places but variables is probably
optional? Would you still recommend to change them everywhere or just
in the idl file?

Do I also have to change the function name exported to the cell, e.g.
OPT_BARRIER()?

> In general, UNOIDL identifiers for enum, constant group, typedef,
> struct, exception, interface, service, and singleton names, for
> struct and exception members, and for polymorphic struct type
> parameters are camel-case starting with uppercase (and interface
> names additionally starting with "X"); identifiers for modules, for
> interface attributes and methods, for service constructors, and for
> interface method and service constructor parameters are camel-case
> starting with lowercase; and identifiers for enum and constant group
> members are all-uppercase with underscores.  (Where the latter is
> the reason why only identifiers starting with lowercase letters and
> containing underscores are reserved for UNO.)

Wow this is tough for my brain :) so from what you've seen anything
else I should change?