Sorting option in core,email and router routes.

[sdimitris]

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update
• Refactor
• Build-related changes
• Other (please describe)

Does this PR introduce a breaking change?

• Yes
• No

The PR fulfills these requirements:

• It's submitted to the main branch
• When resolving a specific issue, it's referenced in the PR's description (e.g. fix #xxx, where "xxx" is the issue number)

Routes which support sorting option:

• /config/modules
• /router/routes
• /router/middlewares
• /email/externalTemplates

[kkopanidis]

if only sort by name is available, name it such. The param should be sortByName and the value should be true or false or something simple in general.