Config goes in $XDG_CONFIG_HOME/beansprout/config.kdl or
$HOME/.config/beansprout/config.kdl
Config is in the kdl format. Right now, the supported options are
```zig
/// Width of window borders in pixels
border_width: u8 = 2,
/// Color of focused window's border in 0xRRGGBBAA or 0xRRGGBB form
border_color_focused: RiverColor = utils.parseRgbaComptime("0x89b4fa"),
/// Color of uffocused windows' borders in 0xRRGGBBAA or 0xRRGGBB form
border_color_unfocused: RiverColor = utils.parseRgbaComptime("0x1e1e2e"),
/// Where a new window should attach, top or bottom of the stack
attach_mode: AttachMode = .top,
/// Should focus change when the cursor moves onto a new window
focus_follows_pointer: bool = true,
/// Should the pointer warp to the center of newly-focused windows
pointer_warp_on_focus_change: bool = true,
```
I plan to add Keybinds shortly. If parsing the configuration fails,
the default config will be used and the WM will continue loading.
