Fix "undefined local variable or method `issue'" bug in issue_patch.rb.
Add the xmlns attribute to the Project element.
Merge branch 'fix-issue_patch_bug'
Replace the disable attribute of uid fields with the readonly attribute.

Controls that are disabled cannot be successful and the values
contained in the disabled controls will never be submitted.

Since the uids fields are disabled and  are not submitted,
the uid_to_issue_id hash created in Import.import_tasks method
are not constructed correctly.
Merge branch 'fix-disabled_uid_field' into buri17_master
Fix invalid default settings.
Change the export rule for Task/ActualWork.

Remove the ActualWork element from the Task element when
the struct.total_spent_hours == 0.
Merge branch 'fix-actual_work' into develop
Merge branch 'fix-init-bug' into develop
Add feature ID settings.
Change ConstraintType from 0 (ASAP) to 2 (Must start on).
Add standard_calendar.yaml to define the standard calendar.
Add duration calculation based on the standard calendar.
Merge branch 'feature-calendar_yaml' into develop
Merge branch 'feature-duration' into develop
Merge branch 'feature-field_id_settings' into develop

Conflicts:
	lib/concerns/export.rb
Merge branch 'fix-constraint' into develop
Modify to call get_sorted_query always in generate_xml.
Merge branch 'fix-query' into develop
Fix wrong week_day in the standard_calendar.yaml.