Build Lantern from source.

Unfortunately the building script fails when trying to rebuild
Lantern.  I'll look into that, but in the meanwhile it's still
valuable to have this.
Get Lantern from a branch, check out in one step.
Fix: check_lantern was killing the building of Lantern.

This is because the Lantern init script doesn't know how to stop
Lantern specifically, so it stops all java processes.  A more
proper fix will be done if this ever makes it into production.
Added some common tasks to readme
Added some common tasks to readme
Remove check_lantern script from this branch.
Merge branch 'git-lantern' of github.com:getlantern/lantern_aws into git-lantern
Add EC2 version of IP getter to README.
Backwards compatibility with master branch.

Parameterize the changes in pillars so we can have machines with
different configurations coexisting.  As a side benefit of doing
it this way, we should be able to change the configuration of
specific machines on the fly.
Fix: had git and installer swapped; other minor stuff.
#1256 Salt changes to support auth token and UDT in fallbacks
Upgrade to salt 0.17.4; various related and unrelated fixes.
#1256 Salt firewall fixes for fallbacks and config.py enhancements
#1256 Added information about config_overrides.py to README
#1256 Added firewall restart after configuration
Pull personal configs into config namespace instead of relying on monkey patching.
Updated README to show better example of config_overrides.py
Fix: stopping Lantern service would kill all java processes.
Merge branch 'git-lantern' of github.com:getlantern/lantern_aws into git-lantern
Backwards compatibility: set new parameters only if Lantern is built from git.