latex/slidenotes: Fix Makefile in sample img/ folder

Add rules for Inkscape. Add Makefile variables for scalable processing.
latex/slidenotes: Ignore LaTeX output files
Add GNOME keyring extractor script in Python
bits: Ignore executable file
crypt: Ignore executable file
emacs: Remove password from gnus configuration file
emacs: Add cs_uso to default channel list for erc
bash: Add "ssh to fep" and "grep-based" aliases
Add CTF folder (Capture the Flag)
Update setuid example