Add file/directory search buttons next to text input

[tsostarics]

Personally i'm fine with typing in the paths to directories and files but i know not everyone is. The text inputs should have little buttons to the left of them to open a file open window, then take the string result from that and update the textinput accordingly. Use the folder-open icon from fontawesome.

[tsostarics]

See file input widget here: https://gallery.shinyapps.io/081-widgets-gallery/

[tsostarics]

I dont think the file input would work unless you select a file within the desired directory, which presupposes that there exists a file in that directory to select, which may not be the case. One of these might work, I'll look in to this more tomorrow

https://community.rstudio.com/t/shiny-directory-input/29160
https://stackoverflow.com/questions/55941597/how-to-select-a-directory-and-output-the-selected-directory-in-r-shiny

[tsostarics]

I'll implement this soon using shinyFiles::shinyDirChoose(), I'm not quite sure why I'm required to use shinyDirButton, but I'll have to do some styling workaround to get it inline the way submitTextButton is currently implement.