1.605 Update - info spots

It's been too long since I've added a new feature so here you go. Info spots are a way to share more about your plans with fellow builders in your group or on the workshop.

- adding a spot saves the current camera position/rotation and brings up a panel to add a note

- exiting or switching from the panel will save the text

- the panel arrows allow moving from spot to spot

- when opening a save the visibility toggle will be on if any info spots are included

- the character count is limited and ',.?! are the only extra characters allowed

- when publishing to the workshop it's possible to not include info spots

Other changes:

- added the water purifier

- allowed for placing under the BBQ and repair bench

- fixed extend floors bug with levels

- fixed some inaccuracies with roof overlap

- the numpad can now be used for part shortcuts (num lock might be needed)

- added the empty propane tank to components in resource count

Suggestions are welcome on here... just saying.