Vanilla lwIP 2.1.2 fetched from https://git.savannah.nongnu.org/git/lwip.git

Branch/Tag: STABLE-2_1_2_RELEASE
SHA1 ID: 159e31b689577dbf69cf0683bbaffbd71fa5ee10

With the following addons:
	- Vanilla lwIP contrib 2.1.0 fetched from https://git.savannah.nongnu.org/git/lwip/lwip-contrib.git (branch/tag: STABLE-2_1_0_RELEASE, sha1id: 35b011d4cf4c4b480f8859c456587a884ec9d287)

Restructured with toki-baseliner, revision 7dc0f8e (dirty).