Optimize Maj() computation in sse2_64

Instead of computing Maj(a, b, c) as (a & b) ^ (a & c) ^ (b & c),
compute it instead as (a & (b ^ c)) ^ (b & c) to reduce the number of
operations.
Optimize Maj() computation in 4way

Instead of computing Maj(a, b, c) as (a & b) ^ (a & c) ^ (b & c),
compute it instead as (a & (b ^ c)) ^ (b & c) to reduce the number of
operations.
cpu-miner: build with jansson 1.x or 2.x
Remove 'hash1' argument from sha256_{cryptopp,c}
autogen.sh: call autoreconf

Hopefully fixes #39 and #40
Merge pull request #36 from verement/master

Optimize Maj() in sse2_64 and 4way algorithms
Merge branch 'master' into debian
Newish version.