doc: tutorial types errors, float not recognized

[cueckoo]

Originally opened by @ghchinoy in cuelang/cue#50

Using types.cue from https://github.com/cuelang/cue/blob/master/doc/tutorial/basics/types.md errors on running cue eval.

$ cue eval -i types.cue 
--- .
unsupported op &((float)*, int):
    ./types.cue:2:8
    ./types.cue:7:10
    
// /home/ghchinoy/dev/cueexperments
{
    point: {
        x:  float
        y:  float
    }
    xaxis: {
        x:  _|_ // unsupported op &((float)*, int)
        y:  float
    }
    yaxis: {
        x:  float
        y:  _|_ // unsupported op &((float)*, int)
    }
    origin: {
        x:  _|_ // unsupported op &((float)*, int)
        y:  _|_ // unsupported op &((float)*, int)
    }
}```

[cueckoo]

Original reply by @mpvl in cuelang/cue#50 (comment)

Ah, there was a recent change to make integer literals not floats. I’ll update the example to use number, the now recommended type to use.

I’m close to finishing some tests for the tutorials to allow catching these kind of things during development.

[cueckoo]

Original reply by @ghchinoy in cuelang/cue#50 (comment)

Thanks @mpvl - please let me know if there's anything I can do to help!