bin: add `git-updateall` to batch `git-pull`

Execute `git pull` in every child directory of the current directory.
Used to pull down the latest changes for multiple repositories in a
project.
bin: add script to open files in Google Chrome
git: add alias to fetch GitHub Pull Requests

`git gh-pr 123`: fetch pull request 123 from `origin`, create a branch
called `gh-pr/123` and then check it out.

`git gh-pr 123 different-remote` will do the same but get the pull
request from the specified remote.
bin: rename and move backup excludes file

Use the common dotfile-ignore naming pattern for the backup ignores too.
shell: use `~/.dotfilesrc` for custom `brew`

Rather than messing around with when to load `~/.bash_profile.local` and
always being mindful of whether a custom `brew` PATH has been sourced,
expect the custom path to be set in a new file: `~/.dotfilesrc`. It can
be used for any up-front configuration that is needed, while
`~/.bash_profile.local` continues to be for local Bash overrides and
settings.
shell: explicit export of PhantomJS bin
Update README
dotfiles: change git remote to ssh

Keep things simple and avoid times when GitHub starts asking for
passwords for `https` again.
vim: fix buggy console vim rendering

The `lines` setting has unintended consequences when using vim in a
terminal. The rendering of lines is all messed up. Moving the `lines`
setting to `.gvimrc` fixes the problem.

Fix gh-22
shell: fix custom `brew` sourcin again
shell: minor tidy up of `bash_profile`
shell: increase cURL max-time to 5 mins

60 seconds is far too short; cURL was aborting downloads of binaries
that Homebrew was trying to install.
Install `bash` with Homebrew

Install the latest version of Bash.
Install packages to convert videos to gifs

Useful for turning screencasts of features or bugs into animated gifs
that can be embedded in READMEs or bug reports.
vim: change indentation 4 -> 2 spaces

Fix gh-29
Add package links to README
vim: disable line wrapping

Prevents the vim UI from getting messed up by long lines, e.g., base64
strings.

Fix gh-30
shell: add `gvim` and `mvim` aliases

Alias these commands so that they always open files in an existing
MacVim window, rather than spawning a new window.
Update submodule 'syntastic' to 3.5.0
Update submodule 'html5' to latest