Fix inputs initialization (#96)
Fix inputs initialization (#96)

* Fix inputs initialization

Try to set `value` to `parameter.value`. Skip if `parameter` was not initialized yet.

* Unify inputs initialization and update

1. Use `setValue()` and `value()` to set and get input value. Create these methods when they don't exist (i.e. text boxes).

dvspirito/pymeasure,ralph-group/pymeasure