influxdb/flux/control
Stuart Carnie 5b58a81700
fix(flux): Flux startup costs should only be paid if Flux is used
This PR lazily initializes Flux built-in functions when Flux is used.

It significantly reduces the startup time of the `influxd` and `influx`
binaries.

Before (4.66s):

```
↳ time bin/18/influx
bin/18/influx  4.66s user 0.19s system 198% cpu 2.441 total
```

After (10ms):

```
↳ time bin/18/influx
bin/18/influx  0.01s user 0.01s system 88% cpu 0.021 total
```
2020-02-03 12:39:00 -07:00
..
controller.go fix(flux): Flux startup costs should only be paid if Flux is used 2020-02-03 12:39:00 -07:00