more sensible mailer option defaults

Conflicts:
	app/mailers/base_mailer.rb
	config/app_config.yml.SAMPLE
	spec/app_config.yml
workaround receive error with many articles
more sensible mailer option defaults

Conflicts:
	app/mailers/base_mailer.rb
	config/app_config.yml.SAMPLE
	spec/app_config.yml
fix shared import paging without query
allow to match category names on import/sync
synchronize price on two decimal places only
allow to synchronize all articles of a shared supplier
query performance improvements