Feat/72/scoresheet download zip

[prphntm63]

• Added functionality to auto-zip requests for more than one scoresheet. Fixed #72
• Added ability for admins to concatenate scoresheets into one PDF per entry number. Fixed #62
• Added ability to request an array of scoresheets (instead of individual)
• Made pdf requests POST based instead of query parameters (#35 pattern)
• Removed/remapped HTML templates (to pug and CSS) (#53 )
• Added method to auto-attach a second page if any data overflowed LIMITT.pdf. Fixed #67
• Cleaned up pdf generator size and tidied CSS to make pages fit on pdf page size perfectly per #67
• Various code cleanup

Sorry for the massive PR :(