Insecure default signature key length

[akwick]

Is your feature request related to a problem? Please describe.
I think that relying on secure defaults is a good approach to minimize insecure code.

Describe the solution you'd like
A user of ESAPI can adapt the key length used in their ESAPI.properties to a desired key length.
However, the default is 1024, e.g., in code. I would like to see a secure default, such as 2048.
Standards, such as the BSI technical guidelines TR-02102-1 state that key lengths of 1024 for signatures should not be used.

Describe alternatives you've considered including other security libraries
An alternative could be a warning that a key length of 1024 is considered insecure for applications that are used now.

Additional context
We, @schlichtig and I, identified this usage during sampling JCA usages and manually reviewing them for the project CamBench. I reached out to @kwwall and @xeno6696 before opening the issue.

[kwwall]

I have already fixed this on my local repo and plan to address it in the next ESAPI release (which is waiting on a dependency). But if anyone is concerned about this in the meantime, just change the ESAPI.properties property Encryptor.DigitalSignatureKeyLength to something like 2048.

[kwwall]

Addressed by PR #809.

[kwwall]

Closed per PR #809. Will be released as part of ESAPI 2.5.3.0.