[scheduled_maintenance] Scheduled maintenance

# Summary

Scheduled maintenance allows users to schedule an upcoming maintenance and show site visitors a warning message in advance.

The first very little tested alpha version is now released.

# Project URL

https://www.drupal.org/project/scheduled_maintenance

# Where is the code?

http://git.drupal.org/project/scheduled_maintenance.git

# Estimated completion date

Unknown.

# Dependencies

None.

# Who's doing the port?

Rade at Druid

# What help do they need?

Unknown.

# D8 roadmap

#2636540: Port to d8

# Background and reference information

N/A