SF-3629 Add support for links with titles

[pmachapman]

This PR adds support for the links with titles, which in Paratext are generated as <link> elements, not the usual <char> element that links without titles are created as. These are used in footnotes and introductions of some translations, particularly the NIV2011.

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This change is 

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 82.91%. Comparing base (12c8136) to head (5b8787c).
⚠️ Report is 1 commits behind head on master.
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3557      +/-   ##
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+ Coverage   82.90%   82.91%   +0.01%     
==========================================
  Files         605      605              
  Lines       36974    36996      +22     
  Branches     6058     6038      -20     
==========================================
+ Hits        30652    30675      +23     
  Misses       5408     5408              
+ Partials      914      913       -1     

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[RaymondLuong3]

This is working well in my testing. Send receive seems to accurately get the content if edits are made around the new link blot. I followed the acceptance tests and could not find any issues

@RaymondLuong3 reviewed 9 of 9 files at r1, all commit messages.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @pmachapman)

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src/SIL.XForge.Scripture/ClientApp/src/app/shared/text/quill-editor-registration/quill-formats/quill-blots.spec.ts line 366 at r1 (raw file):

    });

    it('should set title from contents ignoring an link with  no text', () => {

Nit: typo

Code quote:

ignoring an link 

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src/SIL.XForge.Scripture/usx-sf.rnc line 433 at r1 (raw file):

char.link =
    attribute link-href { xsd:string
        { pattern = "(.*///?(.*/?)+)|((prj:[A-Za-z\-0-9]{3,8} )?[A-Z1-4]{3} \d+:\d+(\-\d+)?[ ]*)|(#[^\s]+)" } }?, # The resource being linked to as a URI

Why is this needed? Are there sometimes whitespace at the end of the href?

Code quote:

?[ ]*)

[pmachapman]

Reviewable status: 8 of 9 files reviewed, 1 unresolved discussion (waiting on @RaymondLuong3)

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src/SIL.XForge.Scripture/usx-sf.rnc line 433 at r1 (raw file):

Previously, RaymondLuong3 (Raymond Luong) wrote…

Why is this needed? Are there sometimes whitespace at the end of the href?

Yes. Because the USFM is in the format \+xt see verse 20|GEN 2:20\+xt*, sometimes users when typing this out in Paratext will leave a space at the end, i.e. \+xt see verse 20|GEN 2:20 \+xt*. PT has no issue using the cross reference in this case, so I thought the best way is just to allow it.

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src/SIL.XForge.Scripture/ClientApp/src/app/shared/text/quill-editor-registration/quill-formats/quill-blots.spec.ts line 366 at r1 (raw file):

Previously, RaymondLuong3 (Raymond Luong) wrote…

Nit: typo

Done. Thanks!