Adjust instruction for setting custom `$ZDOTDIR`.
This addresses 2 potential issues:
- Check for the presence of `$XDG_CONFIG_HOME/zsh` before assigning it to `$ZDOTDIR` instead of blindly assigning
- Avoid recursion in zsh variable assignment stack that might occasionally result in messages like:
```
zsh: job table full or recursion limit exceeded
```
Zsh and Prezto files don't always reside in `~/`. Instead, they have
a more spec compliant location (`${ZDOTDIR:-$HOME}/`). Make them
unambiguous in the documentation. Likewise, for `$GNUPGHOME`.
Further, add instruction for optionally setting up Prezto in
`$XDG_CONFIG_HOME`.
While at this, also add clarification on relative ordering of some of
the modules, apply more formatting tweaks and doc improvements.
We need to accommodate cases where a submodule local path (or remote)
URL can change. Accordingly, update instruction and `zprezto-update`
function to synchronizes submodules' remote URL configuration setting
to the updated value automatically.
General purpose reformating and rewording in (a few places). This should
also make markdown linting happier.
Prefer back-ticks wherever useful and use `console` for code blocks to
be executed on terminal.
Also, update references links wherever possible (including update from
'http://' to 'https://').
* [zprezto-update] Add convenience function to update zprezto
This function checks if there is any update to zprezto, and if so
will pull in the changes. It will not attempt a pull unless
it is fastforwardable. It also makes sure the user is on the master
branch before attempting.
* [zprezto-update] Improve resilience of the function
Better error checking of status of the git repository
and better error producing.
Fit columns into mostly 80 width and add a missing printf
argument.
Use ( ) around the function so changing directory does not affect
the outer scope.
* [README] Add instructions on using zprezto-update function
Explicitly state that a new user must create his own fork to commit and
track changes via Github.
Signed-off-by: Sorin Ionescu <sorin.ionescu@gmail.com>
