CYCLUS_DEBUG_DRE for extra DRE info dump when running simulations

Just set CYCLUS_DEBUG_DRE=1 in your environment when running cyclus to create
tables for information on all request and bids during a simulation in the
database.
another try at a resource buf api

  * it is now templated to reduce casting
  * change all uses of ResourceBuff in cyclus agents to ResBuf
  * use C INFINITY macro instead of custom kInfinity constant
  * PushAll-> Push
  * PopQty -> Pop and it now returns the resources squashed
  * added PopRes and PopNRes methods
  * pending deprecation warn on resourcebuff
  * added a Peek method
added example to doc comments
Merge branch 'dre-dump' of github.com:rwcarlsen/cyclus into rwcarlsen-dre-dump
Merge branch 'rwcarlsen-dre-dump' into develop
nightly build