Transport: Move I2PHMac to ssu package

build.xml

core/java/build.xml

router/java/src/net/i2p/router/transport/udp/I2PHMac.java

...va/src/net/i2p/router/transport/udp/SSUHMACGenerator.java

router/java/src/org/bouncycastle/oldcrypto/Mac.java

router/java/src/org/bouncycastle/oldcrypto/macs/package.html

router/java/src/org/bouncycastle/oldcrypto/package.html