CJSON decode limited to 250 characters

[NicolSpies]

@luismfonseca @marcelstoer This issue was reported and closed as "normal" 7 September last year in #1494.
It appears as if the cjson.decode character limit was reduced or affected between 14 August and 6 September 2016.

This limit did not exist on a dev build just before this date in the build that I have been using since then:

NodeMCU custom build by frightanic.com
branch: dev
commit: 3c55e8c
SSL: false
modules: adc,bit,cjson,enduser_setup,file,gpio,i2c,mdns,mqtt,net,node,rotary,rtctime,sntp,tmr,uart,wifi
build built on: 2016-08-14 09:07
powered by Lua 5.1.4 on SDK 1.5.4.1(39cb9a32)

I have confirmed in this build that the cjson.decode character limit is over 1000 characters compared to the build reported in #1494 and the current dev build where it is limited to 256 characters in line with what was reported in #1494.

[NicolSpies]

In light of CJSON replaced by SJSON #1755, I believe that spending time to fix this will be a waste of time.