A fresh EprimeFrame object has the structure:
tidy(x)
Eprime.LevelName: NA
Eprime.Level: [Level]
Running: [Key]
[Key]: [Value]
[Key].Cycle: [Cycle]
[Key].Sample: [Sample]
These [Key] values make it harder to merge together data-frames later
on, since each unique [Key] gets its own column name. Therefore, we
normalize these field names early on. The end result has the structure:
Eprime.LevelName: [Key]_[Value]
Eprime.Level: [Level]
Running: [Key]
Cycle: [Cycle]
Sample: [Sample]