Add PAUSE sentence doc

Author: boriel

docs/pause.md

@@ -0,0 +1,23 @@
+#PAUSE
+
+##Syntax
+```
+PAUSE <value>
+```
+
+Just as in Sinclair basic, this command pauses the execution for the given number of frames
+(1 frame equals to 1/50th of second in Europe, 1/60th of second in the US: this is usually in
+sync with the electricity AC frecuency) or until a key is pressed.
+
+Bear in mind the number 0 is actually taken as 65536.
+Currently this sentence uses the Sinclair BASIC ROM, so **it needs interruptions enabled**.
+
+Example:
+
+```
+PRINT "Press any key"
+PAUSE 0: REM waits for a Key pressed or for 65536 frames
+```
+
+##Remarks
+* This function is 100% Sinclair BASIC compatible.