Introduce settings page and more options

[stklcode]

This PR covers multiple issues and improvements. Feel free to edit or add.

Most significant change is the introduction of a new settings page. The widget backview is reduced to the two widget-related options (about top lists). I added a link to jump directly to the new page to not annoy existing users that are used to the old config panel.

Second I introduced three new checkboxes to control the skip_tracking behavior. I added the existing blacklist option to this group alongside with "logged in users", "feed" and "search". This partially covers #103, however the remaining options are not controllable yet. Might be combined with @2ndkauboy's solution to allow total control for pro users.
Especially the user agent filter with the RegEx might be suitable to configure here, but this is more of and advanced feature and not that easy to understand.

With the new page, the role filter (#106) can be integrated smoothly.
PR #72 is somewhat obsoleted or has to be adapted to the new method.

Finally two screenshots of the results:

[patrickrobrecht]

Looks quite good. I've just added a commit fixing the text domain and changing some of the descriptions. I'm wondering whether the settings title can be put into <label> for the corresponding inputs - add_settings_field doesn't seem to have an option for that. WP seems to do that on the WP settings pages (except for checkboxes).

Maybe the "skip tracking" options could be displayed as the options on the WP "Discussion" settings page.

[stklcode]

I'm wondering whether the settings title can be put into <label> for the corresponding inputs - add_settings_field doesn't seem to have an option for that.

Sure it does: https://developer.wordpress.org/reference/functions/add_settings_field/

$args
(array) (Optional) Extra arguments used when outputting the field.

• 'label_for'
  (string) When supplied, the setting title will be wrapped in a element, its for attribute populated with this value.
• 'class'
  (string) CSS Class to be added to the element when the field is output.

Default value: array()

Didn't know that until 5 minutes ago, but it obviously works, see latest commit 😃

[stklcode]

The admin menu is yet limited to the manage_options privilega, however the links are shown with edit_dashboard. Bad UX when clicking a link ends up in a permission denied page.

statify/inc/class-statify-settings.php

Lines 289 to 295 in a2b5330

	add_options_page(
	__( 'Statify', 'statify' ),
	__( 'Statify', 'statify' ),
	'manage_options',
	'statify-settings',
	array( __CLASS__, 'create_settings_page' )
	);

I separated the 3 possible permissions:

• See dashboard widget - edit_dashboard or filter statify__user_can_see_stats
• Edit dashboard widget - edit_dashboard
• Edit all settings - manage_options