Default values for settings.

[arthursloan]

When setting up a planner service (and probably device and analyzer services) and defining the various settings it would be beneficial to be able to define a default value for that setting that is communicated back to ARES OS to auto-populate the settings filed, right now, the only options are the name, the data type, whether or not the setting is optional, and a list of values that constrain the available settings.

[nkleiner]

I've got a pull request in draft pending some updates to the data model being merged in and released that gives users the ability to specify default values for their settings. These values will be loaded by ARES upon adding the service, but are overwritten if ARES has other values in it's database that the user set at some point in the past.