Merge pull request #21 from pmienk/develop

Rationalize Makefile.am
Merge pull request #22 from libbitcoin/develop

Develop
VS import props for _protocol.
Merge pull request #23 from evoskuil/develop

VS import props for _protocol.
Merge pull request #24 from libbitcoin/develop

Develop
Add protobuf NuGet dependency.
Merge pull request #25 from evoskuil/develop

Add protobuf NuGet dependency.
Remove redundant _CFLAGS/_LIBADD/_LDADD/PKG_CHECK_MODULES.
Alter calls to make to avoid sending '-j1' argument.
Normalize install script, remove /usr/local pre-install cleanup.