mod(structure): update project structure

Remove examples, add description for design goals in README.md and
apply re-names and naming changes accordingly for the project structure.
Implement a flat hierachry, as the library shall remain pretty simple.

src/cell.zig

@@ -0,0 +1,20 @@
+const std = @import("std");
+const Style = @import("Style.zig");
+
+pub const Cell = @This();
+
+style: Style = .{},
+rune: u8 = ' ',
+
+pub fn eql(this: Cell, other: Cell) bool {
+    return this.rune == other.rune and this.style.eql(other.style);
+}
+
+pub fn reset(this: *Cell) void {
+    this.style = .{ .fg = .default, .bg = .default, .ul = .default, .ul_style = .off };
+    this.rune = ' ';
+}
+
+pub fn value(this: Cell, writer: anytype) !void {
+    try this.style.value(writer, this.rune);
+}