Don't use "class" as a variable name

[rhl@…]

Some structs use "class" as a type/variable/member name (e.g. pmObjects.h). This
is a reserved word in python (and C++), and leads to [surmountable] difficulties
swigging the interface. In this case, changing "class" to "objectClass" is a simple fix.

[eugene]

I changed all of the peaks->class elements to peaks->type; I left the function
named 'pmSourceRoughClass' since the word class is always attached to Rough.