Fix a NRE, and potentially some more.

- Add an option in "mod options" to prefer or force people to only be a guest in one bed at a time.
Be aware that this will behave oddly under certain circumstances, namely when there are more beds than guests. This is a side-effect of how beds choose people (rather than people choosing beds) and how the changes don't happen at the same time, and isn't easily fixable. However, the option may be useful to some people anyhow.

- Tagged as compatible with 1.4. This is untested, but please let me know if it doesn't work and I'll try to fix it.

Add a toggle to show or hide the 'Poly Guest' button to the mod options.

This should help reduce clutter in the common situation where people just want it enabled on everyone.

Fix the new Poly Guest button showing on everything, not just colonists. Oops.

Thanks to MRS0 for reporting it.

Add "Poly Guest" toggle to colonists.

Defaults on, if it's disabled that colonist will no longer be allowed to be a guest in other colonists' beds.

Thanks to Harry for the suggestion.

Fix untranslated "Previous partner" and "Next partner" buttons.

Thanks to Feeeweeegege for pointing it out and mentioning which file needed fixing.

Fix UI buttons disappearing when polygamy mode is enabled without a master.

Hopefully. I didn't actually expect that to work, but it seems to have worked for me.

Colonists will now pick a random valid bed, instead of always using the first.

Colonists should now prefer a valid poly bed if it's occupied, otherwise fall back to their owned bed if they have one, otherwise fall back to any valid poly bed.

[Auto-generated text]: Initial upload.