allow FundtoHirep to compile and link; fix #85

[edbennett]

For a full blow-by-blow of the issue, its debugging, and the thinking behind the solution, see #85, which this PR resolves.

Summary of changes:

• move definition of TFundtoHirep methods into FundtoHirep.hpp from FundtoHirep.cpp
• instantiate the three TFundtoHirep specialisations in FundtoHirep.cpp
• change U._grid to U.Grid() following changes in Grid
• prefix references to Rep::LatticeField with typename to placate compiler
• add new macros to allow the last point to be done in envCreateLat, which adds typename to one but not both arguments

[edbennett]

I've finally been able to log into TeamCity to see what was failing about the Clang build. (I'm not sure if it was an update to TeamCity enabling public access, or if I just didn't notice the "Register" button previously!)

737beec fixes the build with Clang. It now fails to build with Intel, but the error is "configure: error: impossible to compile a minimal Grid program", which I think must be a configuration error? I can't see how I can affect Grid from this repository.