Bash: add grep --color parameter by default
Bash: add shortcut for `du -d 1 -h` command
Bash: source Perforce settings
Fix `.Xdefaults` colors for Solarized theme
URxvt: disable intensity styles

Prevents URxvt from overriding bold/blink styles by high intencity colours.
Remove xscreensaver configuration from `.Xdefaults` as redundant

Xscreensaver is not used anymore. Gnome screensaver used instead.