ENH: Add minimal functionality

Summary

See https://gitlab.indiscale.com/caosdb/customers/lfpb/management/-/issues/381. Review is done in https://gitlab.com/caosdb/caosdb-julialib/-/merge_requests/2

Insert a meaningful description for this merge request here.  What is the
new/changed behavior? Which bug has been fixed? Are there related Issues?

Focus

Point the reviewer to the core of the code change. Where should they start
reading? What should they focus on (e.g. security, performance,
maintainability, user-friendliness, compliance with the specs, finding more
corner cases, concrete questions)?

Test Environment

How to set up a test environment for manual testing?

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Please, prepare your MR for a review. Be sure to write a summary and a focus and create gitlab comments for the reviewer. They should guide the reviewer through the changes, explain your changes and also point out open questions. For further good practices have a look at our review guidelines

• All automated tests pass
• Reference related Issues
• Up-to-date CHANGELOG.md
• Annotations in code (Gitlab comments)
  • Intent of new code
  • Problems with old code
  • Why this implementation?

Check List for the Reviewer

• I understand the intent of this MR
• All automated tests pass
• Up-to-date CHANGELOG.md
• The test environment setup works and the intended behavior is reproducible in the test environment
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For further good practices have a look at our review guidelines.

src/CaosDB.jl

@@ -31,8 +31,9 @@ library_name = (@static Sys.iswindows() ? "ccaosdb" : "libccaosdb")
 
 module Exceptions
 
-export evaluate_return_code, CaosDBException, GenericCaosDBException
+export evaluate_return_code, CaosDBException, GenericCaosDBException, CaosDBMessage
 
+using Logging
 using CaosDB
 
 """
@@ -50,7 +51,19 @@ struct GenericCaosDBException <: CaosDBException
     code::Cint
 end
 
-Base.showerror(io::IO, e::CaosDBException) = print(io, "CaosDBException: ", e.msg)
+Base.showerror(io::IO, e::CaosDBException) =
+    print(io, "CaosDBException: ", e.msg, " (Status code ", e.code, ")")
+
+"""
+Struct containing Messages and codes for status codes<0 that do not
+correspond to errors or success.
+"""
+struct CaosDBMessage
+    msg::String
+    code::Cint
+end
+
+Base.show(io::IO, m::CaosDBMessage) = print(io, m.msg, " (Status code ", m.code, ")")
 
 """
     function evaluate_return_code(code::Cint)
@@ -66,7 +79,11 @@ function evaluate_return_code(code::Cint)
             (Cint,),
             code,
         )
-        throw(GenericCaosDBException(unsafe_string(msg), code))
+        if code > 0
+            throw(GenericCaosDBException(unsafe_string(msg), code))
+        else
+            @info CaosDBMessage(unsafe_string(msg), code)
+        end
     end
 end
 
@@ -180,7 +197,7 @@ function create_plain_password_authenticator(
         password,
     )
 
-    CaosDB.Excepions.evaluate_return_code(err_code)
+    CaosDB.Exceptions.evaluate_return_code(err_code)
 
     return auth