More solid block content decoding
Update CHANGELOG
Use DataUtil API for checking if content is serialised
Merge pull request #1618 from Guite/1.3

This PR was merged into zikula:1.3 branch.

Discussion
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More solid block content decoding

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | https://github.com/Guite/MostGenerator/issues/499
| Refs tickets  | 
| License       | MIT
| Doc PR        | 

Commits
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05a3297f684222ad068ebfe4db66c2815b36bb42 More solid block content decoding Guite
918b15f4443d74562c4ef338151762e7c60819fe Update CHANGELOG Guite
ace4f3684482830d5b206f073055e7c84442f44f Use DataUtil API for checking if content is serialised Guite