* tower_* modules: move HAS_TOWER_CLI in TowerModule
Besides this change allows to define other common parameters such as
mutually_exclusive.
* tower_*: config file can not be used with auth params
* tower module_utils: remove useless call to expanduser
'path' type: expanduser & expandvars are automatically called
* fix typos
* use formatting functions
* use 'job template' instead of 'job_template'
* acronyms: user uppercase
* become_enabled param is about privilege escalation