[sr-dev] new feature: update sip msg content in request route

Hello, I just committed a new function in modules_k/textops - msg_apply_changes(). Hopefully the name is suggestive enough - the function applies the changes done to the content of sip message - e.g., if you added a new header, once you use the function, that header will become visible in config file. Therefore the function tries to overcome the overhead of looping various messages back to sip server just because modifications were not visible once done. Another benefit is ability to access latest value for a field (being header or body content) in case of need to hashes or signatures for security purposes. The function can be used only in request route for now. Be carefully when using it, since it changes the expectation you had so far of always working on initially received sip message. Once the function is sued, initial content is lost forever. Since it builds a new buffer and re-parses, it is not very recommended to use it extensively. Example of usage: append_hf("My-Header: yes\r\n"); if(msg_apply_changes()) { # msg buffer has a new content if(is_present_hf("My-Header")) { # will get always here } } Testing and feedback is welcome! Cheers, Daniel