Support cache disabling

tests/tmath.nim

@@ -7,6 +7,7 @@ type
   mingw_dbl_type_t = object
 
 cDebug()
+cDisableCaching()
 
 cAddStdDir()
 cImport cSearchPath("math.h")

tests/tnimterop_c.nim

@@ -2,6 +2,7 @@ import std/unittest
 import nimterop/cimport
 
 cDebug()
+cDisableCaching()
 
 cDefine("FORCE")
 cIncludeDir "$projpath/include"

tests/tnimterop_cpp.nim

@@ -2,6 +2,7 @@ import nimterop/cimport
 import unittest
 
 cDebug()
+cDisableCaching()
 
 cIncludeDir "$projpath/include"
 cAddSearchDir "$projpath/include"

tests/tsoloud.nim

@@ -3,6 +3,7 @@ import os, nimterop/[cimport, git]
 gitPull("https://github.com/jarikomppa/soloud", "soloud", "include/*\nsrc/*\n")
 
 cDebug()
+cDisableCaching()
 
 const
   inc = "soloud/include"