removed xsede and swc pages. replaced html code with markdown equivalents

content/events/2016/hcc_fall_kickstart_2016.md

content/events/2016/hcc_qiime_workshop_2016.md

content/events/2016/hcc_spring_workshop_uno.md

...nt/events/2016/instructions_for_52016_allinea_workshop.md

...pentry_open_science_grid_workshop_unl_january_6_8_2016.md

...s/2016/software_carpentry_workshop_uno_july_14_15_2016.md

content/events/2016/xsede_workshop_big_data_november_2016.md

content/events/2016/xsede_workshop_openacc_december_2016.md