GenCode - Add an optional caching mode.

If CIVICRM_GENCODE_DIGEST is set, then GenCode will write out a digest of
all its inputs & templates. If someone tries to rerun with the same inputs,
then GenCode will do nothing.
GenCode - Cleanup
setup.conf.txt - Add suggestions about CIVICRM_GENCODE_DIGEST
Merge pull request #2340 from totten/master-cache-codegen

GenCode - Add an optional caching mode.
CRM-14080 default to now

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* CRM-14080: Have noticed there is no default on received_date on contribution.create - should default to now
  http://issues.civicrm.org/jira/browse/CRM-14080
Merge pull request #2349 from eileenmcnaughton/CRM-14080

CRM-14080 default to now
GenCode - Ignore cache/digest if some key files are missing
Merge pull request #2353 from totten/master-cache-codegen2

GenCode - Ignore cache/digest if some key files are missing
Merge branch 'master' of git://github.com/civicrm/civicrm-core into CRM-13981
CRM-13981, handling profile selector for mixed profile types in Edit and Copy case

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* CRM-13981: Migrate "In Honor of" to Soft Credits
  http://issues.civicrm.org/jira/browse/CRM-13981