[#519] Update source install docs for 2.0

Update the source install and related docs (datastore setup, solr setup,
testing) and files (deployment.ini_tmp, test-core.ini) for CKAN 2.0.

The idea is to document the setup process that OKFN is currently using
on its servers, so that the deployment docs can become the docs for the
OKFN dev team and we can dogfood our own docs, instead of having a bunch
of wiki pages, READMEs, etc. that we follow and ignoring the "official"
docs. Hopefully those can all be deleted or cut down massively once this
is done.

So both the docs now describe the layout we use on our servers, where
there's space for multiple CKAN sites on the same server, with
virtualenvs in /usr/lib/ckan/ and config files in /etc/ckan/.

- Changed default virtualenv location from `~/pyenv` to `/usr/lib/ckan/default`

- Changed default config files dir to `/etc/ckan/default`

- Added tip for developers in source install docsS symlink `/usr/lib/ckan` and
  `/etc/ckan` to directories in your homedir to install ckan in your homedir

- Changed default database user from `ckanuser` to `ckan_default`

- Changed default database from `ckan_dev` to `ckan_default`

- Changed default datastore database from `datastore` to `datastore_default`

- Changed default datastore database user from `readonlyuser` to `datastore_default`

- Changed default test databases from `ckan_test` and `ckan_test_datastore` to
  `ckan_test` and `datastore_test`

- Changed default `ckan.site_id` from `ckan.net` to `default`

- Disabled file log handler, rely on Apache's log files only (as we do on our
  servers)

- Changed the docs to use restructured text substitutions for things like the
  paths to the virtualenv and config files, database names, etc. instead of
  typing them out each time

- Lots of minor formatting fixes and editing

So now we have:

    virtualenv:        /usr/lib/ckan/default
    development.ini:   /etc/ckan/default/development.ini
    production.ini:    /etc/ckan/default/production.ini
    ckan.site_id:      default
    Database user:     ckan_default
    Database:          ckan_default
    Datastore user:    datastore_default
    Datastore db:      datastore_default
    Test database:     ckan_test
    Test datastore db: datastore_test
[#519] Update post-installation docs

Make them fit with the changes in commit
6e1d325d61ea66cd197864dc9a5af5c65af183c0
[#519] Update deployment docs

Uses the same directory structure as the updated source install docs, so
you can step through the source install docs and then the deployment
docs as written and it all works.

Also updated the apache.wsgi and sites-available files to match those
that we use on our servers.

Removed CORS setup instructions as this has been builtin since CKAN 1.5.
[#519] Edit source install docs

Minor edits to install from source docs
[#519] Edit solr setup docs

Minor edits to solr setup docs
[#519] Update FileStore setup instructions
[#519] Fix Travis build

Update the database and user names in travis build
[#519] Minor edits to solr setup docs
[#519] Add postfix to deployment docs
[#519] Minor edits to datastore docs

Minor edits to the datastore docs, from Dominik. See:

https://github.com/okfn/ckan/pull/807
[#519] Docs: change restart_apache substitution to reload_apache
[#519] Docs: use the reload_apache substitution
[#519] Remove non-root URL deployment instructions

We've had reports from some users that this causes problems with some
CKAN features, so we don't want to recommend it until tested.
[#519] Replace seanh with `whoami` in source install docs
[#519] Docs: changed 'supported' to 'recommended'
Merge pull request #874 from okfn/519-update-deployment-docs-second-try

519 update deployment docs second try