lots of new features and updates_2

[R-Abbasi]

• changes in generateTrainingData.cpp:
  • warning popup if nothing suitable to upload is chosen beforehand
  • select a file and its data will be set into the fields
  • fields are then grayed-out
  • fields with no data from the file are capable of taking data
  • fields with data from file are read-only
  • fields get back to default settings if Waveform From File radio button is unchecked
  • fields show the data again if Waveform From File radio button is checked again
  • data of the chosen file from the Devices & Waveforms Menu is set to the fields as soon as it's checked
    • fields get back to default settings if the file is unchecked
    • fields get back to default settings if a device ID is selected or if neither of the radio buttons is checked
    • choose a device ID of the current waveform, optionaly feed the fields and upload data
  • The data is sent to the url https://postapi.aw4null.de/v1/uploadFile/ if the Send button is clicked
  • a message pop ups informing the user of the result of the data upload
  • data will also be written to a .json file to be able to observe the uploaded data (optional)
• modified saves_popup.hpp to saves_popup.cpp
• extended the language maps (inside newly created header languages.hpp) to support the generateTrainingData popup completely
• modified sendData.hpp to upload data
• used an enum class for the key of the languages std::maps since string literal comparisons might not always be correct.
• and more ...

PS: Didn't touch the part for which suggested a method for refactoring PS2: Only the changes in saves_popup.cpp (earlier saves_popup.hpp) are not shown correctly, probably due to renaming, not sure though. captureData was used there instead of sampler. The rest is almost alike.