Fix handling long Reason Phrase

rfc2616 does not specify the maximum length of *Reason Phrase* so it's
a good practice to handle even unreasonably long input.

16 char. buffer is not enough to correctly handle even the common `304
Moved Permanently`. Increase buffer size to more realistic 32. Also, up
to 128 more characters will be read and ignored, providing even greater
versatility without increasing memory usage.

Issue #163
Tests for "Fix handling long Reason Phrase"

Issue #163
Merge pull request #164 from dpc/issue-163

Fix Issue 163