Improves visual identification for sensors
- [x] Docs
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* target db_schema
* Database schema cleanup
Remove several inconsistencies (mostly with data types and lengths)
Make things a bit nicer to implement with Laravel database migrations.
poller* tables had f'd up indexes
* Update tests, extra noise because db returns numeric types now.
* Update test data again.
* fix 253 migration for mysql 5.3
Tony Murray
CZ