fixing ifdef/elif construct around prototypes in transceiver.c
added missing FCS to IEEE802.15.4 adaptation layer
updated ICMPv6 types from I-D to RFC values
Merge pull request #149 from OlegHahm/transceiver_prototypes

fixing ifdef/elif construct around prototypes in transceiver.c
Merge pull request #150 from OlegHahm/6lowpan_plugtest_fixes

6lowpan plugtest fixes
added the release notes for 2013.08
updated license headers

(No code changes!)
Merge pull request #152 from OlegHahm/release_note

added the release notes for 2013.08