Manage positions page #611

[nahom70]

Fixes issue #644

Changes

• Created a positions route in the main route.
• Queried data from positions history to filter the active positions in history and pass to managepositions.html
• Edited demo data for position history, tweaked the attributes there to match the model.
• Added managepositions.css where some CSS logic is handled
• Added managepositions.js where the datatable logic is handled

Testing

• Worked around the data and UI through inspection
• Made sure the passed data is displayed by cross-checking on the database.