When serializing, length field is always zero

[kastork]

In the dis_sender.py, the emitted ESPDU has its length field set to zero.

The code in that example doesn't manipulate the length field.

This matters if you're using, say, open-dis java's PduFactory#getPdusFromBundle()`, which relies on this field's value.

[leif81]

Thank-you for the report @kastork

Setting the length seems like something that should be done automatically by the library.

Can I interest you in submitting a pull request?

[kastork]

I doubt I'll have time to, I'm not really making a python application, was just kicking the tires and learning.

[leif81]

Here's an example for how length is calculated in open-dis-java

https://github.com/open-dis/open-dis-java/blob/master/src/main/java/edu/nps/moves/dis/EntityStatePdu.java#L61

[VovaDev]

Currently working on it. Will file PR within day or two.
PS: Also found some crtitcal typos (like when variable initialized as munitionExpendableID and used as munitionExpendibleID)