Undo-tree & tabbar modes added. Euchy-aliases!

- Keyboard config for Windows and Linux separated
- Many defalias'es
- More shortcuts:
  1. C-S-o to expand current window by killing the neighbour
  2. H-k to kill this buffer and C-S-k to kill neighbour buffer
  3. Use  to highlight matching parens
  4. C-g for magit-status
  5. C-c <left> and C-c <right> for cycling around tabs\

More importantly, H-o for C-x o!!