v0.4.2

Fixes:

• ReplaceRequestTagsString and ReplaceHeaderTagsString methods now return an error apart from the result to allow code using them to decide if substitution is critical or not.

  This is used to send a response to the client when the hash_key.pattern can not be processed due to some HTTP request part missing, that implies the hashkey can not be calculated in a consistent matter so the backend neither

• The buffer for the HTTP headers reader is now pre-allocated with the size set by user's configuration before peeking the headers from it, avoiding overflows

Contributors:
@achetronic