sync with svn

- change default backend registration order
- mangle resume argument as BPRESUME
- code clean-up (avoid warning about ref. class assignment to local variable)
- version and NEWS bump
improve output of error traceback
Merge commit '504f622b8a591863458ce7167671ad05a157c7cb'
clean up setGenerics

- no {} so reported as 'standardGeneric'
Delete pvectorize.R (superseded by bpvectorize)
removed pvectorize from collate
re-added missing parenthesis
started specialization for bplapply
SerialParam and MulticoreParam.
updated docs
pass ... in MulticoreParam
reverted patch to not evaluate symbols too eagerly
Add test for return value on empty list