Merge pull request #5 from pooler/master

0.8.3.7 gitian sigs from pooler
0.8.3.7 gitian sigs from thrasher
Merge pull request #6 from thrasher-/master

0.8.3.7 gitian sigs from thrasher
Update Litecoin gitian.sigs.ltc instructions
0.8.4.1 gitian sigs from wtogami
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0.8.4.1 gitian sigs from weex
Merge pull request #7 from weex/master

0.8.4.1 gitian sigs from weex