Adding an option to get annotations

[A3EKV]

Currently the annotations are missing in mendeley_cli. Is there any reason to limit it only to:

 documents      
 documenttypes  
 files         
 groups        
 token         

Notice also that according to Mendeley API (https://api.mendeley.com/apidocs/docs) the groups API is deprecated.

[shuichiro-makigaki]

Basic annotation support is included mendeley-python-sdk that is used internally in Mendeley CLI, but it does not support filtering by user document ID and Group ID. Additionally, mendeley-python-sdk does not support Groups v2 API usage.

Very sadly, upstream development of mendeley-python-sdk is almost stopped for years, and we cannot expect to add the features that we need.

Therefore, I have to start forked (Yet-Another) Mendeley SDK: https://github.com/shuichiro-makigaki/yandeley-python-sdk.

After adding the required features, I will start to implement Mendely CLI.