cluda/dtypes: added detect_type() with the common pattern of checking value data type
transformations: more accurate type detection in scale_const()
cluda/dtypes: fixed bug when double precision floats were truncated in c_constant()
fft.mako: removed unnecessary int -> float transformation
fft.mako: fixed argument type of complex_exp() which screwed up FFT precision. Fixes #2
Merge ../tigger