remove directory permission checking, since cli can handle this for us
call ->database() instead ->mysql()
update usage() add db_driver option
add default value for db_driver to mysqli
correct variable name and cli argument name to match with model/install.php
fix indent style
correct path to "download" directory
correct path to "download" directory
add DIR_MODIFICATION
set default db_prefix to "oc_"
https://github.com/opencart/opencart/issues/1105
https://github.com/opencart/opencart/pull/1210
Merge pull request #1209 from ball6847/fix_cli_installer

Fix cli_installer.php
fixed customer approve on checkout register
fix for https://github.com/opencart/opencart/issues/1096
minor css changes
Fixed the variable for trial frequency check in the profile_form.tpl
Fixed variable name issue for trail period in recurring.php model when storing to database.