Change frontmatter to be more standard

content/articles/2010/a1-contest-2010.md

content/articles/2010/antenni-prepinac-na-vkv-20.md

content/articles/2010/attiro-20-vyvojovy-kit-pro-atmega8.md

...ent/articles/2010/bezpecny-regulovatelny-zdroj-s-lm317.md

content/articles/2010/cq-world-wide-dx-cw-2010.md

content/articles/2010/cq-world-wide-wpx-cw-2010.md

content/articles/2010/digitalni-hodiny-s-atmega8.md

content/articles/2010/drawdio-kreslime-zvuk.md

content/articles/2010/i-subregional-2010.md

content/articles/2010/ii-subregional-2010.md

...nt/articles/2010/klicovani-pro-majaky-beacon-keyer-v10.md

content/articles/2010/konvertory-a-redukce-smd-pouzder.md

content/articles/2010/led-srdce.md

.../mistrovstvi-cr-deti-a-mladeze-a-radioelektronice-2010.md

content/articles/2010/ok-dx-rtty-contest-2010.md

content/articles/2010/provozni-aktiv-2-2010.md

content/articles/2010/q-kody.md

.../soutez-deti-a-mladeze-v-elektronice-karlovy-vary-2010.md

content/articles/2010/univerzalni-sekvencer.md

content/articles/2010/vhf-contest-2010.md