Add empty seq example and collection documentation links

[codeconscious]

My second PR, created in the hopes of improving this wonderful cheat sheet. Any suggestions or feedback are welcome.

Summary:

• Adds examples for creating empty sequences via CEs (per F# 9 release notes)
• Adds links to collection documentation
• Minor text tweaks (for consistency, etc.)

[bartelink]

Added some feedback - having links is useful in general, but every line here needs to earn its keep; this is a cheatsheet, not a shorter version of the overall docs.

There's a related discussion on #19

I added comments to #12 and would be likely to merge edits based on my earlier opinions as expressed on that

Unfortunately it's not ideal that there's just you and me paying attention (@SpiralOSS is obviously busy; not sure if @charlesroddie has time and/or interest atm), but I'm happy to err on letting things be added and tweaked for now and generally clearing down the issues list, with a later round of compacting the text and/or aggressively trimming examples to the minimum possible balancing things out.

[codeconscious]

Added some feedback - having links is useful in general, but every line here needs to earn its keep; this is a cheatsheet, not a shorter version of the overall docs.

Sure, that's fair. Thanks for the note. (I admit to being a bit eager to add helpful info. This is me holding back! 😆) I'll have a look at the linked issues to get some context too.

[SpiralOSS]

Thanks, @codeconscious! I fell off this to focus on Datastar, so really appreciate it.

[bartelink]

Thanks!