made it possible to call a function from a library

Conflicts:
	htdocs/install/mysql/tables/llx_cronjob.sql
	scripts/cron/cron_run_jobs.php
add the libname field in the migration script

Conflicts:
	htdocs/install/mysql/migration/3.4.0-3.5.0.sql
indentation
Merge pull request #1075 from csalvador/modcron

Modcron