vim: update vimrc
vim: update vimrc

1. Update indention about shell: indent 2 spaces and no tabs.

2. `colorscheme solarized` will raise error before install plugin.
  It blocked install script. In this case, I use `silent!` to ignore
  error.

3. Highlight current line with DarkBlue.

4. Set dark background for solarized scheme.

fhfuwei/dotfiles,0x04C2/dotfiles