Presubmission final changes

See merge request es/autosubmit!263

Presubmission changes ( sleep was triggered for all jobs instead of only if hold directive is present)

Fixed #683: We should now take finish time from the function input instead of time()

Closes #683

See merge request es/autosubmit!261

Improved verification of current experiment run in the historical database.

See merge request !260

Added documentation for the custom shebang feature.

See merge request !258

Tweaks autostartdate

See merge request !259

The previous implementation of structure did not consider jobs that did not...

See merge request !257

The previous implementation of structure did not consider jobs that did not have any dependency, resulting in an unnecessary execution of transitive reduction every time the experiment is monitored. It is now fixed.

Changed Copyright year, added more documentation.

See merge request !256