Spaces, not tabs.

Actually, I liked tabs much more. But it seems a lot
of IDEs and general reader do not handle them correctly,
or do not let you configure "1 tab == 4 spaces", so the code
was not always readable.

"git diff -w" for this commit is en empty list.

Signed-off-by: Luca Fulchir <luker@fenrirproject.org>

We compile on FreeBSD 10.3 now.

Signed-off-by: Luca Fulchir <luker@fenrirproject.org>

tell people to get the LZ4 library correctly

Signed-off-by: Luca Fulchir <luker@fenrirproject.org>

Build, make deterministic and statically link the
lz4 library if necessary.

Signed-off-by: Luca Fulchir <luker@fenrirproject.org>

Quite a messy commit, hopefully new ones should be shorter

Signed-off-by: Luca Fulchir <luker@fenrirproject.org>

Rewrote cmake, now a bit cleaner, checks for compiler flags.

Added Eigen3, v3.2.8 in case it's not found on the system.

Signed-off-by: Luca Fulchir <luker@fenrirproject.org>

Also add relative (optional) cmake target: "docs"
Documentation is still incomplete, needs more
work.

Signed-off-by: Luca Fulchir <luker@fenrirproject.org>