Support Zabbix 4

[kmpm]

Just making an issue of it.

[saumyajit]

Hi kmpm,

Thanks for the code. It really nice to have a simpler but useful UI. But facing issue using in 4.0.x . Only getting graph for an hour. Whatever the time range i may select, it's giving only last 1 hour's graph. Kindly suggest how can i fix this issue.

Thanks again.