Merge pull request arduino-libraries#122 from per1234/fix-file_println-docs

Replace irrelevant function name in `File::println` docs

Author: per1234

docs/api.md

@@ -451,7 +451,7 @@ Print data, followed by a carriage return and newline, to the File, which must h
 ```
 file.println()
 file.println(data)
-file.print(data, BASE)
+file.println(data, BASE)
 ```
 
 #### Parameters
@@ -887,4 +887,4 @@ void printDirectory(File dir, int numTabs) {
 * [read()](#read)
 * [write()](#write)
 * [isDirectory()](#isdirectory)
-* [openNextFile()](#opennextfile)
+* [openNextFile()](#opennextfile)