Number fixes (#1053)

* cleaning up the logic for parsing numbers

* Add Testcases for new Reader in jsontestrunner 
diff --git a/meson.build b/meson.build
index aa50d8f..8531dce 100644
--- a/meson.build
+++ b/meson.build
@@ -15,7 +15,7 @@
     'cpp_std=c++11',
     'warning_level=1'],
   license : 'Public Domain',
-  meson_version : '>= 0.50.0')
+  meson_version : '>= 0.49.0')
 
 
 jsoncpp_headers = [