Add extractingText, which extracts text content of given nodes #192

[keesvandieren]

Solves #192 .

Added tests for various XML inputs.

Let me know if any adaptations are needed.

[coveralls]

Coverage increased (+0.02%) to 91.841% when pulling 8f913cf on squins:multiple-nodes-extracting-text into cf0e547 on xmlunit:main.

[keesvandieren]

@bodewig I do not understand why one of the builds fails. I've looked into it, it seems that test-compilation fails because it cannot find my newly added method extractingText, but for just one build. If you can look into it and guide me if I should change anything, that would be great :-)

[bodewig]

TBH I don't see the reason at first glance either. Will have to take a closer look, but it may take until the weekend before I find time to do so.

Thank you, BTW :-)

[bodewig]

The compat tests passed locally, so I assume there has been some oddity in the Travis a wrong SNAPSHOT version has managed to slip into the local maven repo. We'll see what happens after the build of the main branch is through.

Many thanks!