+20080816
+ + add configure option --enable-weak-symbols to turn on new feature.
+ + add configure-check for availability of weak symbols.
+ + modify linkage with pthread library to use weak symbols so that
+ applications not linked to that library will not use the mutexes,
+ etc. This relies on gcc, and may be platform-specific (patch by Dr
+ Werner Fink).
+ + add note to INSTALL to document limitation of renaming of tic library
+ using the --with-ticlib configure option (report by Dr Werner Fink).
+ + document (in manpage) why tputs does not detect I/O errors (prompted
+ by comments by Samuel Thibault).
+ + fix remaining warnings from Klocwork report.
+