Provide a flag to control case sensitivity for individual Glossary terms

### Describe the problem

Our translators have complained that they are getting unjustified check errors with a number of glossary terms which only have the (glossary-intended) meaning when they appear in a certain casing (e.g. "SHIFT" or "Enter") but they must not be matched in a case-insensitive way (like when used as verbs in regular sentences).
There are other terms though, where an insensitive case matching is desired - so a per-glossary option doesn't help.

Having a flag to control this would be perfect.