* tweak utils.Merge docs
* move merge_test to utils_test package for easier testing
* utils: support MergeConfig and StructFieldFilter
* constrain updating certain fields by the restricted system admin
* MM-14442: Merge function, to enable merging of configs
Merge will return a new struct of the same type as base and
patch, with patch merged into base. Specifically, patch's values will be preferred
except when patch's value is `nil`.
Restrictions/guarantees:
- base or patch will not be modified
- base and patch can be pointers or values
- base and patch must be the same type
- base and patch must have no unexported types (at the moment)
- if maps or slices are different, the entire map or slice will be
replaced (at the moment)
* License header
* major rewrite addressing PR comments from Jesse
* MM-14442: merge function for config files
- simplified merge for slices and maps
- fixed many problems with nested pointers/maps/slices
- all references are cloned
- 54 new tests, simplified tests for specific problems
* MM-14442: fixing formatting, comments
* TestGetLicenseFileFromDisk: avoid using fileutils.FindConfigFile
* config: abstract config-related file access, extend memory store
* simplify config validate to avoid file knowledge
* fix relative file tests
* cluster: fix ConfigChanged event
The old and new configurations were swapped when notifying the enterprise code of configuration changes, creating needless instability in propagating config updates across a cluster.
* config/database: ignore duplicates
* test cleanup
* remove unnecessary Save() in test
* vendor github.com/jmoiron/sqlx
* MM-11262: introduce a database store
* revert unnecessary fmt.Errorf
* simplify unit test helper methods
* remote TODO re: retry
* relocate initializeConfigurationsTable for clarity
* factor out a commonStore
* acquire database config lock on close for safety
* add missing header
* fix lock comment
