Naming conflict

Created by: martinloren

Please change:

template <size_t CAPACITY>

into

template <size_t JSON_CAPACITY>

(or other else) and rename all CAPACITY to JSON_CAPACITY. The issue is that CAPACITY is too generic and used in other Frameworks that conflict with this library. Thanks!

In particular it conflict with STM32 HAL Library (stm32f4xx_hal_mmc.h) which define:

#define CAPACITY 0x400000U /*!< Log Block Number for 2 G bytes Cards */