Clam Client v2.1.0-beta.1 release

Beta release of Clam client v2.1.0. Clam codebase was reworked into a newer version of the bitcoin codebase. Gitian build checksums below

1d2c5175adebf3432b98118a68096b4ffed8b47a852abd93b9526625b5b03691  clam-2.1.0-aarch64-linux-gnu.tar.gz
7efc5a6ec891ef0ea9ba8255e0d6741879b3f13e98a78a69c43e72f6d617e6f4  clam-2.1.0-arm-linux-gnueabihf.tar.gz
781506744dcda52cda3d0a313d7c4797a11a8ce5a910da2fa3f8400fb9cdb321  clam-2.1.0-i686-pc-linux-gnu.tar.gz
d704148787432181da63f54b761a94aa98a1dc28772e1028b93bc8142d29a04e  clam-2.1.0-x86_64-linux-gnu.tar.gz
8ca9016dcc93d59f10454efafac31e44717dc22ef4a04812caeeabdd5fa7ffb4  clam-2.1.0-win32.zip
4acaafae24f9490b501520422654b6e42acef343416e2f4d6ebf5912ab0674bf  clam-2.1.0-win64.zip
c49b90f8ee70c4cb60fdb4bb78451dd8ef9d13ec16b79042c32626ac16bacc9b  clam-2.1.0-osx-unsigned.dmg
be652eec167e0733d2e14e2e3d0f56a6eb59f841034de41e060d5d07dc48bfdf  src/clam-2.1.0.tar.gz