Fix reader not skipping over all CRLF

[thatstoasty]

From my message in Discord:

We should check if content-length > 0 before trying to read the body, and we should also skip any leading \r\n before reading the body. There was a leading \r\n that consumed 2 bytes that was expected in the body itself

[saviorand]

Looks good, also appreciate the unit test! Made one small tweak to server logic so the user actually sees the errors in dev when we throw internal server error, see resolved comments.
Merging now and shipping a new release