Added custom implementation of strtod() (issue #453)

fuzzing/Makefile

@@ -7,7 +7,7 @@ all: \
 	$(OUT)/json_fuzzer_seed_corpus.zip \
 	$(OUT)/json_fuzzer.options
 
-$(OUT)/json_fuzzer: fuzzer.cpp
+$(OUT)/json_fuzzer: fuzzer.cpp $(shell find ../include -type f)
 	$(CXX) $(CXXFLAGS) $< -o$@ $(LIB_FUZZING_ENGINE)
 
 $(OUT)/json_fuzzer_seed_corpus.zip: seed_corpus/*

fuzzing/seed_corpus/Numbers.json

@@ -14,5 +14,11 @@
   12.34e+56,
   12.34E56,
   12.34E-56,
-  12.34E+56
+  12.34E+56,
+  NaN,
+  -NaN,
+  +NaN,
+  Infinity,
+  +Infinity,
+  -Infinity
 ]