* unix/tclUnixNotfy.c: fixed event/io threading problems by

	making triggerPipe non-blocking

	* library/tcltest1.0/tcltest.tcl:
	* generic/tclThreadTest.c: fixed mem leaks in threads

	* generic/tclResult.c: fixed Tcl_AppendResultVA so it only
	iterates once over the va_list (avoiding a memcpy of it,
	which is not portable).

	* generic/regc_color.c: fixed mem leak and assertion, from HS

	* generic/tclCompile.c: removed savedChar trick that appeared to
	be causing a segv when the literal table was released

	* tests/string.test:
	* generic/tclCmdMZ.c: fixed [string index] to return ByteArrayObj
	when indexing into one (test case string-5.16) [Bug: 2871]