Plan AAF Improvements

[ckunki]

• https://github.com/exasol/advanced-analytics-framework/issues/176
• https://github.com/exasol/advanced-analytics-framework/issues/178
• https://github.com/exasol/advanced-analytics-framework/issues/177
• https://github.com/exasol/advanced-analytics-framework/issues/176
• https://github.com/exasol/advanced-analytics-framework/issues/175
• https://github.com/exasol/advanced-analytics-framework/issues/174
• https://github.com/exasol/advanced-analytics-framework/issues/180