Usage of vector with abstract eltype

[dkarrasch]

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This came up in a nanosoldier run. I noticed that in this line, a vector is allocated whose eltype is abstract, since there is no eltype to Givens:

https://github.com/RalphAS/GenericSchur.jl/blob/48bff3566cbbe923742ef7bb249ffd739117cd2e/src/symtridiag.jl#L74

In every subsequent setindex!, this calls a convert routine (which does nothing I guess), but in case it's possible, it may be beneficial to precompute the correct eltype and set it upfront?

[RalphAS]

Thanks, I'll put that in the next patch.