FENNEL: Fixes for cygwin in SqlStrCastFromApprox and FromExact. snprintf on cygwin is older, has different return values. This should be correct for cygwin and linux. Unit tests still fail due to other issues.
FENNEL:
Fixes for cygwin in SqlStrCastFromApprox and FromExact. snprintf on cygwin is older, has
different return values. This should be correct for cygwin and linux. Unit tests still
fail due to other issues.

[git-p4: depot-paths = "//open/dt/dev/": change = 2664]

LucidDB/luciddb,LucidDB/luciddb,LucidDB/luciddb,LucidDB/luciddb,LucidDB/luciddb,LucidDB/luciddb,LucidDB/luciddb,LucidDB/luciddb,LucidDB/luciddb