Accessibility: Differentiate navigation landmarks in front-end templates

[mercime]

We have twenty navigation landmarks throughout the bp-legacy templates. Add one or more navigation landmarks from the theme side, that can get confusing for users of assistive technologies.

We need to clarify what our navigation landmarks are in relation to the other navigation landmarks and the whole screen by adding aria-labels.

[mercime]

Attached patch gives a general overview of each primary and secondary navigation elements. We could make each specific e.g. Group settings menu, Member profile menu, etc. What do you think? :)

[mercime]

Add overlooked navigation landmarks

[DJPaul]

When these go in, can we update BP-Nouveau with these? Any accessibility enhancements we make with BP-Legacy should be copied into BP-Nouveau where they can/

[mercime]

@DJPaul Yes. I have also mentioned to hnla that I contribute to bp-nouveau after BP 2.7 rolls out :)

Updated patch removes navigation role for Group create tabs and changes menu for navigation.

[mercime]

In 11128:

Accessibility: Differentiate navigation landmarks for screen readers.

Fixes #7256.

[dcavins]

In 11137:

Specify text domain in string translation function.

Fixes problem with bp-legacy/groups/index.php introduced in r11128.

See #7256.

[r-a-y]

In 11148:

bp-legacy: Add back missing <ul> in Members Directory template part.

See r11128.

See #7256.

[mercime]

In 11170:

Add navigation role to profile field group links in Profile > Edit screen.

See #7256.

[mercime]

In 11172:

Correct the value for aria-label in commit r11170.

Antiprops mercime.
See #7256.