Autotool-ified the 'lastpass-cli' project.

Autotools build system to replace the hand-rolled Makefile. 

agent.c - had some issue with this compilation due too 'struct ucred' not being defined. I did not check to see if it was supposed to be a system defined struct, so I inverted the first pound-if check.

ASCIIDOC was not included in my patch as I didn't want to open the autoconf manual. Just as well, users should not be building the manual pages and the actual manual (as well as asciidoc text file) should be in the repository. Very rarely do contributors need to update the documentation for simple bugs and no one likes another force-fed dependency.

Forgot to mention- to actually bootstrap the project, run "autoreconf -i" and "configure" will be output in the same directory.

Then its just
./configure
make 
make install