Ensure HOME environmental variable set

When working with puppet (and other setups), it is possible the HOME environmental variable is unset. This
leads to a spf13 bootstrap which does not perform as expected because `$HOME` is empty. This results in files being written to undesirable locations such as `/.spf13-vim-3/.vimrc.bundles` Let's stop the user before they get into this bad state.
Add support for Salt files
Adopting the Apache 2 License. Fixed #653
Merge pull request #667 from dustinrc/saltstack

Add support for Salt files
Merge pull request #664 from jinnovate/HOME-set

Ensure HOME environmental variable set
replace iunmap <CR> with inoremap <CR> <CR>

If noninvasive completion is set, i get the following error:

Error detected while processing ~/.vimrc:
line  730:
E31: No such mapping
Press ENTER or type command to continue

To avoid this "no such mapping" error, instead of unmapping the commands for <CR> one can simply overwrite it with itself to reset it, which works regardless of wether the mapping existed or not.
Merge pull request #669 from wolfgangpfnuer/patch-1

replace iunmap <CR> with inoremap <CR> <CR>
created "puppet" bundle.
fixed echo command
removed Puppet-Syntax-Highlighting as it's antiquated and not maintained
Merge pull request #672 from shoekstra/fix_echo

fixed echo command
Merge pull request #671 from shoekstra/add_bundle_for_puppet

Add "puppet" bundle.
Update README.markdown

Added information from this forum topic on how to add a bundle to the list: https://groups.google.com/forum/#!searchin/spf13-vim-discuss/install/spf13-vim-discuss/s_PMWxVVogM/otCEQs0ZlsYJ
Merge pull request #675 from jaguarondi/patch-1

Update README.markdown