boost extensions: Add orthogonalization functions and tests.
boost extensions: Add orthonormalization functions and normalize function.
doc: Update documentation.
test: Update tests for array-versions of orthogonalization and orthonormalization functions.
boost extensions: Add return value code for concat_vectors when the number of vectors passed is zero.
fixme: Add FIXME keywords for later fix-up.
Merge pull request #121 from Makman2/boost_extensions

Boost extensions