Reviewers: dev-osl_imageworks.com, osl-dev_googlegroups.com,

Description:
Add a new opcode that computes sin and cos together

Please review this at http://codereview.appspot.com/205045/show

Affected files:
src/liboslcomp/typecheck.cpp
src/liboslexec/master.cpp
src/liboslexec/opmathfunc.cpp
src/liboslexec/oslops.h
testsuite/trig/ref/out.txt
testsuite/trig/test.osl