Memory management issues

[Enchufa2]

Minimal reprex. First, we generate a bunch of data:

library(simmer)

traj <- trajectory() %>%
  timeout(1)

env <- simmer() %>%
  add_generator("asdfasdfasdf", traj, function() rexp(100, 1)) %>%
  run(1e7)

We can see that the R session takes up now more than 1 GB. Two problems arise:

1. Resetting the environment clears the internal objects (monitoring data, etc.), but does not deallocate the memory.
2. rming the environment seems not to finalise the internal objects.

[Enchufa2]

#99 fixes 1. Related to 2: tidyverse/magrittr#146