[ieboilstart] add set type

[kbjarkefur]

Default var type

You can have different default values for when creating numeric vars. This actually can make a difference when generating random numbers as if the type is set to float you get more precision with more decimals on your random number. With iesave this should not lead to inefficiencies in disk space with storing data.
set type float, permanently

Default random number generator

Include set rng default to make sure the default RNG mt64 is used.

[kbjarkefur]

Actually when testing, the scope of set rng is:

The scope of set rng is the Stata session, do-file, or program in which rng is set.

Same as version. So to have this make any difference the command needs to return the setting to be run outside the command. Like how the command handles version. I think that is overkill for set rng as the scope is also Stata session. This mean that if anyone change the default for a session it is set back to the default the next time Stata is opened. So it will only be used where it is intentional.