v2.7

• Determine received record length automatically, a pre-determined record length is no longer needed.
• Support M SEED quality code.
• Support for IPv6 connections, conversion to pure getaddrinfo() usage.
• Allow host and port to be separated with '@', e.g. host@port to allow for numeric IPv6 address usage.
• Update Makefile to include an install method, common shared target.
• Add buffer scanning limit fix from Andrei Akimov.
• Fix segfault in sl_msr_print() when no record passed.
• Include socket level timeout that defaults to 60 seconds.
• Incorporate platform-specific declarations into libslink.h
• Remove support for Watcom-related wmake files.
• Change licensing to Apache License 2.