Handle longer form training e.g Masters courses

[njall]

EJP-RD and HDRUK want to use TeSS to aggregate content. For HDRUK they want to collect training from their multiple member institutes. For EJP-RD they want to collect training about their area of interest (Rare-disease).

They both contain longer-form courses than TeSS typically represents. The scope of TeSS has been focused around short-form training. Additionally, chronological representations of upcoming courses will be distorted by year long courses. All year, masters courses will be presented at the top of the page making for worse usability.

If the length of a course >3 months, filter out from the index. Have a search option to display these long courses, and allow widgets/API to show long-form courses so that they can be shown in the widgets HDRUK/EJP-RD will adopt.