Oracle DataBase module

execution module; can connect to multiple dbs described in pillar and
run sql-query
fix some pylint warnings
fix some pylint warnings
rewrite dict comprehension
allow hierarchical credentials

used for store 'default' and 'sys as sysdba' database connection:
my_db:
uri: user/pass@host/db
dba:
uri: sys/syspass@host/db as sysdba

oracle.run_query my_db:dba "select * from dba_users"
avoid confusing with salt-cloud
rewrite some sentences
add document for installing salt-cloud on Ubuntu

as saying that salt cloud is merged to Salt may cause confusing
make user thinks no need to install salt-cloud pkg
add basic usage doc for salt-cloud
Consolidate duplicate bind docs of docker.running

The documentation for `docker.running` had two divergent definitions for the `bind` argument. I've consolidated them and added some explanation of the two forms.
add lxc integration tests
modules.lxc: fix referenced before assignment error
use a faster template (sshd) for lxc integration tests
Clean keyboard exit in test suite
Add missing <ul>[…]</ul> around list elements in sidebar TOC.
Updated the contributing guide with a link to the documentation contribution docs.
Fixed some spacing issues in the contributing docs.
Fixed regression that messed up Road Keep data directory
Added jobber stack in prep for refactor of jobber channel
Merge pull request #14104 from SmithSamuelM/sam_raet_50

Fixed regression that messed up Road Keep data directory
Merge pull request #14097 from mgwilliams/lxc

add lxc integration tests