Inconsistent use of variable names

[a-dekker]

Running the Alpha branch for a while now, no big issues. One thing I did notice is that some json keys changed their name which broke some tools I run based on the output.
pvfrequentie is now called pvfrequency. It is indeed better to use English terms instead of Dutch given the audience. But the pvfrequentie name is still used all over the place.
Another issue I encountered is the pvipmtemperature key. A lot of times it is referred to as the incorrect pvimptemperature key in the code.

A simple search/replace in the codebase should fix this.

[johanmeijer]

Thanks. I will change it. Luckely, for compatibility reasons, we can define multiple Keys pointing to the same register content.

Sometimes it is difficult for a dyslexic like me to be consistent with naming. Sorry for that.