Get rid of id from report and custom search urls

For reports:
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1. Add a name column to report_instance table.

2. A combination of name and report_id column would be used to uniquely identify an instance, which would also require adding a unique constraint for this combination.

3. Under report criteria section of template add a form field which would accept the value for name column. The field would look like -
Path: civicrm/report/instance/contact/summary/____abcd_______
where abcd would be stored as value for name.

4. Fix report instance invoke file to also work with urls with names (in addition to ids) like - http://example.com/civicrm/report/instance/contact/summary/abcd

For custom searches:
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Currently name and label stores same values in option value table for custom searches. We could use existing name column to store / accept custom search names.

1. On manage custom search screen add another field to accept the value for name column.
The field would look like -
Path: contact/search/custom/____abcd_______

2. Fix custom search invoke file to also work with name urls like - http://example.com/civicrm/contact/search/custom/abcd