install-chef-suse: Do not use /tmp, but a directory created with mktemp
Add json-edit utility

This is a small tool that can be used to set the value of an attribute
in json. It will create the parent attributes if needed, and the file if
it doesn't exist.
install-chef-suse: Do not modify data bags from barclamps

Modifying them is quite bad as it means that on updates, either the
change is lost or the changes from the updates are lost.

Instead, we simply create minimal json files with the changes we need,
and we reference them from the crowbar proposal so that they get used.
Remove now unneeded bc-dns-json.rb and bc-provisioner-json.rb tools
install-chef-suse: Allow a minimal crowbar.json

We can configure already the things we want to change compared to the
default crowbar data bag, to allow crowbar.json to be minimal.
install-chef-suse: Mark crowbar user as disabled if not in crowbar.json

If the crowbar user got removed from crowbar.json, then we need to mark
it as disabled so that its presence in the default crowbar data bag can
be ignored.
Use new crowbar-deep-merge-template attribute for incomplete json
Add now-open dell_raid and dell_bios to the opensource Pebbles builds
Merge pull request #1870 from VictorLowther/pull-req-opensource-dell-and-raid

Add now-open dell_raid and dell_bios to the opensource Pebbles builds
Merge pull request #1872 from vuntz/install-chef-suse-rework

Rework how we change default proposals in install-chef-suse
Update pebbles/cloudera-build to use dell_bios instead of bios.
install-chef-suse: Stop removing redhat_install/ubuntu_install

This is not in the crowbar json template anymore, so no need to make
them empty in crowbar.json.
install-chef-suse: Use network config from /etc/crowbar/network.json

If /etc/crowbar/network.json exists, then we want to use this as the
network configuration (with deep merge).
json-edit: Add ability to remove attributes
json-edit: Spacing fixes
json-edit: Fix setting/removing of some non-existing subattributes

If there's already an attribute like foo.bar set to "test", then it was
failing when trying to do something on the foo.bar.foo attribute.

Now, when setting, we overwrite foo.bar to be a hash, and when removing
we just exit early.
install-chef-suse: Also call bc-network-admin-helper.rb on network.json

When we have network.json in /etc/crowbar, we also need to validate it.
[Devguide] Formatting tweaks

* Line wrap at 80 characters
* Remove trailing whitespace
* Properly indent HTML table
* Remove bullet for "Before submitting pull requests...", since
  there's only one item
[Devguide] Add links to the community Ruby and Rails style guides
Merge pull request #1878 from jamestyj/master-style-guide

[Devguide] Add links to community Ruby and Rails style guides