minor documentation

Fixes copypaste error in file_put_contents documentation, documents system_is_tablet, system_is_chromebook and DIRECTORY_TEMP.

doc/src/references/builtin/Environment/Global Properties/system_is_chromebook.nvgt

@@ -0,0 +1,12 @@
+/**
+	This property is true if the application is running on a Google Chromebook.
+	const bool system_is_chromebook;
+*/
+
+// example:
+void main() {
+	if(system_is_chromebook)
+		alert("example", "This application is running on a chromebook!");
+	else
+		alert("example", "This application is not running on a chromebook.");
+}

doc/src/references/builtin/Environment/Global Properties/system_is_tablet.nvgt

@@ -0,0 +1,12 @@
+/**
+	This property is true if the application is running on any device that identifies itself as a tablet.
+	const bool system_is_tablet;
+*/
+
+// example:
+void main() {
+	if(system_is_tablet)
+		alert("example", "This application is running on a tablet!");
+	else
+		alert("example", "This application is not running on a tablet.");
+}

doc/src/references/builtin/Filesystem/Functions/file_put_contents.nvgt

@@ -11,7 +11,7 @@
 
 // Example:
 void main() {
-	if (!put_file_contents("example.txt", "This is an example"))
+	if (!file_put_contents("example.txt", "This is an example"))
 		alert("Example", "Failed to write the file.");
 	else
 		alert("Example", "Successfully wrote the example file.");

doc/src/references/builtin/Filesystem/Global Properties/DIRECTORY_TEMP.nvgt

@@ -0,0 +1,16 @@
+/**
+	Property that returns the system's temporary directory, a place where short-term data can be stored.
+	const string DIRECTORY_TEMP;
+	## remarks:
+		A slash character is already appended to the directory returned by this property.
+		This function may return different values depending on the operating system the application is being run on.
+			* On Windows, usually C:\Users\%username%\appdata\local\temp/.
+			* on macOS and Linux systems, usually /tmp/.
+			* on Android, the app's cache path.
+		In any case the directory returned should be writable, though you should expect things you store there to be deleted by external factors at any time.
+*/
+
+// example:
+void main() {
+	alert("example", "a temporary file for the game could be stored at " + DIRECTORY_TEMP + "filename.txt");
+}