Fix build error caused by pthread lib order

https://github.com/BVLC/caffe/issues/1327
Merge pull request #1332 from tleyden/master

[fix] set pthread last in build order
[docs] cite the arXiv paper
[docs] BVLC Caffe acknowledgements
[docs] re-title docs, count forks
Merge remote-tracking branch 'upstream/master'

Conflicts:
	Makefile