ODBC backend plugin

[flo91]

The read-access to ODBC data sources is working, unit tests are present and a new command kdb mountOdbc was added to provide basic mount functionality for ODBC data sources.

Work in progress / open:

• implement write functionality --> will be done in new PR
• implement support for binary values --> will be done in new PR

Done:

• implement metadata support
• offer more configuration options (e.g. table- and column-names)
• remove hardcoded mountpoint for the ODBC backend
• update tooling to allow the creation of user-defined mountpoints for the ODBC backend
  • new kdb mountOdbc command added
• extend documentation
  • comprehensive Tutorial written
• add tests

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[flo91]

jenkins build libelektra please

[flo91]

jenkins build libelektra please

[flo91]

@atmaxinger I've now addressed the issues that you've mentioned in your review and did some other bugfixes. Additionally, I also wrote a manpage for the kdb mountOdbc command.

[markus2330]

@flo91 great work, looking forward to follow-up. Didn't test it yet.

@kodebach thx for the review!

@hannes99 please rework arguments of mount odbc as discussed (also make odbc a subcommand as suggested by @kodebach).