Bug fixes

eye 1.2.1

• if no eye column is found, eyes also returns a list #31
• set_eye_strings also updates eye column #32
• partial eye strings recognized in column names #33
• to_etdrs now correctly always returns integer class vector #34
• conversion of pure "NA" saved as character now correctly returns NA #35
• logMAR will return rounded values to the first digit when noplus = TRUE #37
• to_etdrs from pure qualitative values correctly returns 0 for NPL and PL #38