add entry message wide string support

[goatshriek]

Implements stumpless_set_entry_message_str_w and fixes some wide string functionality as well.

This is a continuation of #376, which implemented most of this functionality but had a few problems remaining, and has since gone stale.

This fixes #272, which can be referenced for more information.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 90.91%. Comparing base (aef696d) to head (eed1e65).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## latest #412 +/- ## ========================================== + Coverage 90.61% 90.91% +0.29% ========================================== Files 47 47 Lines 4307 4326 +19 Branches 572 574 +2 ========================================== + Hits 3903 3933 +30 + Misses 278 264 -14 - Partials 126 129 +3 ```

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[goatshriek]

@rmknan, this pull is the completion of your previous one. Please feel free to provide a review of it, particularly since it is almost entirely derived from your work. I'll leave it open for a week to give you some time to comment before merging it in.

[sonarcloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud