```boost()``` does not deal with ```sol(299792458)```

[RobinHankin]

> sol(299792458)
[1] 299792458
> u <- as.3vel(c(1e8,0,0))
> u
         x y z
[1,] 1e+08 0 0
> boost(u)
           t          x y z
t  1.0607520 -0.3538288 0 0
x -0.3538288  1.0607520 0 0
y  0.0000000  0.0000000 1 0
z  0.0000000  0.0000000 0 1
> 

The top row should be a 4-velocity in SI (the speed of light is set to its value in meters per second) so should be about 10^8. Also need more documentation describing the sign of this term.

[RobinHankin]

Also is.consistent.boost() does not work if the speed of light is not 1:

> sol(100)
[1] 100
> c(10,30,40) %>% as.3vel %>% boost  %>% is.consistent.boost
[1] FALSE
> 

[RobinHankin]

> c(10,30,40) %>% as.3vel %>% boost  %>% is.consistent.boost
[1] TRUE
>