Add retry_failures option to config
(#482)
Need to remove current_val, otherwise the subsequent tries will just use the cached value.
(#482)
Add example of retry_failures to demo8
(#482)
Add comments in demo scripts about new retry_failures option
(#482)
Add retry_io option to config output field
(#482)
Add retry_io to list of ignore params in other places.
(#482)
typo
(#482)
Clearer warning text for retry_io option
(#482)
Merge branch 'nobj_bug' into #482
Switch sequence indexing scheme within a file to start at 0 at the start of each file.
(#482)
Merge branch 'master' into #482

Conflicts:
	galsim/config/value.py
Add Sum type for value_types where it is sensible
(#482)
Add Sum type to config tests
(#482)
Use Sum type for shear in demo9.
(#482)
Improve description in galsim executable
(#482)
Add option to add or modify variables on galsim command line
(#482)
Add items to CHANGELOG
(#482)
Fix bug where 'safe' objects were not being correctly invalidated after reading in a new catalog

Conflicts:
	CHANGELOG.md
	HISTORY.md
	galsim/config/process.py
Update check_json to only run one config file at a time
(#482)
Add noclobber check for demo9.json to the call in check_json using the new command-line variable feature
(#482)