Submodule updates.
Adds Tmux usage subchapters:

- Basic interaction
- Scroll, copy and paste
Removes unused fish functions and renames other ones.

Signed-off-by: Claudio Ortolina <claudio@jumpzero.com>
Adds Backspace fix to .vimrc
Removes Fish shell support.

Signed-off-by: Claudio Ortolina <claudio@jumpzero.com>
Adds .inputrc.
Fixes capitalization typo.
Adds small note for `gf`.
Adds paragraph about ctrl-p.
Updates submodules.
Forces Vim to regenerate help tags when opening.
Adds extra docs:

- Rails.vim
- Tmux integration
Fixes wrong h2.
Title hierarchy fixes.
Fixes typo.
Typo fix.
Adds paragraph about reading from shell.
Adds misc gifs.
Indentation fixes.
Updates Tmux theme.