add default preference for max tab limit in staff client

[Ben Shum]

Evergreen version: master

Add default preference for max tabs in staff client to prefs.js. By default, this is set to 0 for unlimited tabs. Including this setting will allow staff client packagers to more easily assign a limit if desired.

Some reasons for adding a tab limit may include:

  1) avoiding memory exhaustion - opening too many tabs can be bad
  2) preserving staff sanity - do not have too many tabs open at once

[Ben Shum (bshum)]

Working branch for master: http://git.evergreen-ils.org/?p=working/Evergreen.git;a=shortlog;h=refs/heads/user/bshum/lp932295-max-tab-limit-setting

[Thomas Berezansky (tsbere)]

This is a good idea, if only to raise potential awareness that it can be changed. Committed!