Inital work for task #9098 - `provide subject id in report`
Pass unittest with attribute `lab_id`
Improve error message `There is no subjects in the raw data`
+ Cleanup extra imports
+ No functionality changes
Reformat xml for easy reading in `test/TestCreateEmptyEventTreeForStudy.py`
Modify `create_empty_event_tree_for_study()`
to copy `lab_id` as a `person` element attribute
Remove unused file: `bin/utils/report.xsd`
Add the original subject id - `lab_id` to the summary report
TODO:
 - sort by lab_id
 - fix test/TestGenerateOutput.py
Add configuration option to allow sorting by lab_id or redcap_id
Cleanup unnecessary code in `test/TestCreateSummaryReport.py`
Improve comment in `bin/redi.py` about `create_summary_report()`
Note: no functionality changes
Fix `bin/utils/report.xsl` to implement sorting by: `lab_id/redcap_id`
Move caption outside the `thead` in `bin/utils/report.xsl`
Use `Subject ID/Subject Number` as column headers
Remove developer specific details from main README.md
Add more links to existing files in the `doc/` folder from README.md
Add the removed pieces from README.md as seprate files
in the `doc/` folder
Link to our code review guidelines `doc/code-review-checklist.md`
from the main README.md
Link to Philip's RED-I presentation from the main README.md
Fix anchors for document sections in README.md
Rules for clearing values using keyword 'cancel'