FreeBSD relayd

Building

env LIBCRYPTO=... LIBSSL=... LIBTLS=... LOCALBASE=... OPENSSLINCDIR=... PREFIX=... ./configure
make

The latest tested LibreSSL version is 3.7.2.

Use freebsd-relayd: prefix in commit message.
Use #if __FreeBSD__, #endif to make FreeBSD specific blocks in source files.
Use # BEGIN FreeBSD-relayd, # END FreeBSD-relayd comments to make FreeBSD specific blocks in makefiles and configuration files

Add the OpenBSD repository as a remote.

git remote add openbsd git@github.com:openbsd/src.git

Pull the master branch from the openbsd remote and track it as openbsdmaster.
```
git fetch openbsd
git checkout -b openbsdmaster --track openbsd/master
```
Find the details needed for the final branch name.

The name of the final branch should be in the form of the following scheme:
```
OSMAJOR.OSMINOR.LATEST_COMMIT_DATE
```
OSMAJOR and OSMINOR are major and minor versions set in the OpenBSD source tree in the master branch. LATEST_COMMIT_DATE is the commit date of the latest OpenBSD commit in the master branch (e.g., 2014.08.10).

The OSMAJOR and OSMINOR values can be found in share/mk/sys.mk:
```
grep "OSM\(AJOR\|INOR\)=" share/mk/sys.mk
```
LATEST_COMMIT_DATE can be obtained with the following command:
```
git show --quiet HEAD | grep "Date:"
```

Rename the release branch to OSMAJOR.OSMINOR.LATEST_COMMIT_DATE.

git branch -m "release" "OSMAJOR.OSMINOR.LATEST_COMMIT_DATE"

Rebase and merge the final branch (OSMAJOR.OSMINOR.LATEST_COMMIT_DATE) on top the openbsdmaster branch.
```
git rebase --merge openbsdmaster
```
Resolve conflicts if needed.
Check the build process.
```
./configure
make
```
Test relayd.

Currently, the testing procedure is not autmated. Testing should include the following steps:
1. Create a configuration file for relayd.
2. Check the configuration file's syntax: relayd -n -v -f <config>.
3. Run relayd: relayd -d -v -f <config>.

Publish the final branch to the freebsd-relayd repository.

git push --set-upstream freebsd-relayd `OSMAJOR.OSMINOR.LATEST_COMMIT_DATE`