Remember the last "Steam user id" selection

[idbrii]

Is your feature request related to a problem? Please describe.
Every time I use boilr, I need to select my "Steam user id"

Describe the solution you'd like

1. When I select "Steam user id" from the drop down at the top, write the selected id to a file.
2. When boilr starts up, select that id if it exists in the list.

Describe alternatives you've considered
Only use boilr with one steam account. But the other steam accounts aren't controlled by me, so that doesn't work.

Last tried on v1.9.1