fix: warn this is a pre-alpha release
fix: add -Wall to linker options
new: add .gitignore
fix: for some reason, the initialization and deinitialization functions of shared library is not working in the same way under
glibc 2.14 (gentoo) and glibc 2.12 (CentOS 6). So this fix implement another way to initialize KRB5 default keytab for GSSAPI