Fix linking of libkunquat tests.
Make reading of numbers locale-independent.
Fix incorrect rounding in some tests.
Fix locale-specific behaviour in serialisation of floats.
Make integer serialisation portable.
Clean up.
Use portable integer serialisation with pattern instance references, fractions and timestamps.
Merge pull request #108 from kagu/fix_readfloat

Fix conversions between floats and strings in libkunquat