Reduce the trial length

[jml]

From @Futurile

I'd like to move Weave Cloud to 14 day trial ASAP. I'd also like to
reduce the time period before we block them from sending us new data.
How fast can we do the engineering?

The impact will be that this will accelerate users through the system to
either convert or terminate their trial. I've resisted it previously as
I felt that it was too short to actually try the product: but Customer
Success can extend trials so lets try it.

This is not sufficient, but it's enough to get a serious engineer started. Still to do:

• actually test this
  • find an instance currently in trial and verify that this does not change the trial period
  • create a new instance and verify that it has the new, shorter trial period
• find any copy on service-ui that refers to these times and update it

[rndstr]

• verify email reminders go out at expected times (which they should, they are configured to go out N days before expiration)

---

I also set TrialExtensionDuration to 7d (which was previously 15d) which comes into play when enabling billing for someone where previously billing wasn't enabled which should rarely happen since we enable billing for everyone by dfeault

[rndstr]

here is the project for the website part: https://github.com/weaveworks/marketing/projects/10
thanks @soschwei!

find any copy on service-ui that refers to these times and update it

there is no mention of 30 in service-ui.

Edit; also, I would suggest we merge/deploy this PR after changing the copy everywhere.

[rndstr]

Planned to go out after Friday 8am PDT (1600 BST)

@leth feel free to merge as soon as your Friday prod deployment is over to have this sit in dev for a couple hours

[soschwei]

@rndstr there is one mentioning of the trial on the service: https://cloud.weave.works/signup Just making sure you didn't overlook.

[leth]

Thanks @soschwei: I've raised https://github.com/weaveworks/service-ui/pull/3161