Bump tcltest version to 2.3.6 (should have been done just before the 8.5.15 release, just as in Tcl 8.6.1). 
Don't fix eol-style for Makefile.in in "make dist", if the file system is case-insensitive/case-preserving.
Don't fix eol-style for Makefile.in in "make dist", if the file system is case-insensitive/case-preserving.