Fixed bugs:

• Importing an error containing library in library causeed dead lock on multithread environment. #159
• get-bytevector-all with buffered port ignored buffered values. #160
• Subtract negative rational number from zero returned positive number. #161
• Loading FFI library from child thread raised an error. #163
• (expt 5 10000000) caused SEGV. #162
• compare procedure passed to er-macro-transformer returned #t even the given 2 arguments are not the same.
• syntax-case expander contained incorrect use of free-identifier=?.
• Reading more than one byte from standard input port on Windows returned incorrect number of values.

Improvements:

• TLS socket port is now bidirectional port.
• Windows file port can also read from COM now.
• Displaying big integers of radix 2, 8 and 16 takes O(n) order. (n = size of bignum)
• Displaying big integers of other radixes is now much faster than before.

New features:

• (sagittarius termios) has been added. Not documented.
• `smtp-login-authentication for LOGIN method has been added to (rfc smtp).