Always fill upper or lower of triangular/symmetric/Hermitian matrices

[termoshtt]

Inherit from #74, related to #226

LAPACK routines for triangular, symmetric, Hermitian matrices, e.g. dsyev, only read and write to upper or lower part of storage. This is why we have to manage UPLO enum noted in #74. This is basically performance issue, but we should nod expose such partially invalid storage even if additional runtime cost is inevitable.

Alternative

We may resolve this problem by introducing a partially written storage for this issue. But it will be better to use packed storage #226.