Do more of line simplification with integer coordinates (#113)

* Turn off unit, which has bit-rotted

* Instrument line simplification

* Do more work in integer space

* Update tests with simplification done with more integers

* Clean up

* Update changelog

* Eradicate calls to deprecated sprintf()

* Revert "Turn off unit, which has bit-rotted"

This reverts commit 998779313f.

* Fix catch by switching to an unsigned type

text.cpp

@@ -46,7 +46,7 @@ std::string check_utf8(std::string s) {
 					out += " ";
 				}
 				char tmp[6];
-				sprintf(tmp, "0x%02X", s[i + j] & 0xFF);
+				snprintf(tmp, sizeof(tmp), "0x%02X", s[i + j] & 0xFF);
 				out += std::string(tmp);
 			}
 			out += ")";