CSAW CTF 2014: link to ‘Obscurity’ write-up

Closes #131.
CSAW CTF 2014: link to write-ups on sugarstack.io

Closes #130.
CSAW CTF 2014: update list of completed write-ups
CSAW CTF 2014: link to write-ups by tasteless

Closes #129.
CSAW CTF 2014: link to write-ups by @shankaraman

Closes #133, #134, #135, and #136.
CSAW CTF 2014: add ‘Shameless plug’ write-up

Closes #137.