Add Wesley Shields to AUTHORS and CONTRIBUTORS
Merge branch 'master' into richpe
Implement yr_calloc() and switch yr_malloc() back.

Implement a yr_calloc() which uses calloc() internally. In the WIN32 case it
just calls yr_malloc() which passes the HEAP_ZERO_MEMORY flag already.

Make yr_malloc() use malloc() internally.

Switch the places in the pe module which need zero'ed memory to using the
new yr_calloc().