eina: cleanup and merge code for sin and cos.
eina: cleanup and merge code for sin and cos.

NOTE: this patch is part of the previous attempt to fix
rounding error. Hopefully things are better now.


SVN revision: 71150

turran/eina,gfriloux/eina,gfriloux/eina,turran/eina,turran/eina,gfriloux/eina