Removed "Last Modified" entry in file comments.

It's really just not necessary when using git.
Re-work to use backtrace() system calls.

Use the backtrace() and backtrace_symbols() system calls rather
than manually specifying function names. Also drop support for
dynamic flub allocation. This dramatically simplifies the API
for the end-users and simplifies the backend implementation.
It is also hoped that the information supplied by official system
calls will be more useful than what the end-user is both willing
and able to provide at any given point.

The new API is not compatible with the old API, but I'm the only
person who uses this (I think) so far, so, who cares, right?
Use JavaDoc-like comments in header file.

I've decided that JavaDoc looks prettier (or maybe it's just more
familiar to me).

Either way, it's a bit difficult for Doxygen to generate sane
documentation with all the macro-magic going on in here. Oh well.
Install to '/usr/local' directory.

The old install scripts installed libflub to the '/usr' directory,
but only the package manager should install to that directory; use
'/usr/local' instead.
Update library major number.