agg results must get their formatter from the aggConfig
[discover/fieldChooser] remove code that doesn't do anything
[aggConfig] always use the number format for metric results
[hierarchical/collectBuckets/tests] fix stubbed aggConfigs
[indexPattern/fields] expose sortable and filterable properties on field objects
updated field fixtures to support sortable and filterable properties
Merge branch 'master' into fix/2047

Conflicts:
	test/unit/fixtures/stubbed_logstash_index_pattern.js
Merge pull request #2113 from spenceralger/fix/2047

Fix #2047