znt: optimizations for zsh<=5.2

Vault basic autocompletion

forklift: update homepage URL and tweak formatting

Add OSX support for command-not-found

chruby plugin locals moved inside function

Re-added $ZSH_THEME_GIT_PROMPT_EQUAL_REMOTE

Re-added $ZSH_THEME_GIT_PROMPT_EQUAL_REMOTE variable which was removed in 9f552130

Close #4740

Put `local var` declaration in its own line in lib/git.zsh

In places, the local statement will override the exit code and the written
command won't have the effect intended when it was written.

For example, when it's not inside a git repo the exit code won't be true,
but the local statement will make it true regardless. See #4708.

Add hub's completion file

Fixed a typo.

colored-man-pages: Use Portable `less` Path

Update gulp.plugin.zsh

Remove `local` stuff that cause an error in shell

This uses the version at commit 35c76bf (2015-12-08)
https://github.com/github/hub/commit/35c76bf91dc3d699173599464b9b41cb877ee440

Commit 09d2a597 introduced the bug, which is due to using
single brackets conditions at the same time as *.

This commit should fix it and use double brackets everywhere
else.

Fixes #4699

Fetch Gulp tasks list in a better way

Add local stuff

Sort pipe dropped and fix 2>/dev/null

znt: more optimizing workarounds for 5.0.6 <= zsh < 5.2

Close #4469

Some environments (in my case, cygwin) have PATH variables with directories
with spaces in them, breaking colored-man.
Adding quotes around the PATH environment variable makes the plugin run OK.

Close #4103

When the user is asked to update oh-my-zsh it says "[Oh My Zsh] Would
you like to check for updates? [Y/n]:". When the user agreed to update
the next text would say "Upgrading Oh My Zsh" which is inconsistent
with the question.

Nicer formatting of ember aliases in README

Update frontcube.zsh-theme

Git: move current_branch() to core