printf docs and other small docs tidies

doc/source/reference/language/builtin_functions.rst

@@ -52,7 +52,7 @@ returns the const table of the VM.
 
 .. js:function:: setconsttable(table)
 
-sets the const table of the VM. And returns the previous const table.
+sets the const table of the VM; returns the previous const table.
 
 .. js:function:: assert(exp)
 
@@ -60,7 +60,7 @@ throws an exception if exp is null
 
 .. js:function:: print(x)
 
-prints x in the standard output
+prints x to the standard output
 
 .. js:function:: error(x)
 

doc/source/stdlib/stdstringlib.rst

@@ -18,7 +18,7 @@ Global Symbols
 
     returns `true` if the end of the string `str`  matches a the string `cmp` otherwise returns `false`
 	
-.. js:function:: ecape(str)
+.. js:function:: escape(str)
 
     Returns a string with backslashes before characters that need to be escaped(`\",\a,\b,\t,\n,\v,\f,\r,\\,\",\',\0,\xnn`).
 
@@ -28,10 +28,18 @@ Global Symbols
     The format string follows the same rules as the `printf` family of
     standard C functions( the "*" is not supported). ::
 
-        eg.
+        e.g.
         sq> print(format("%s %d 0x%02X\n","this is a test :",123,10));
         this is a test : 123 0x0A
 
+.. js:function:: printf(formatstr, ...)
+
+    Just like calling `print(format(formatstr` as in the example above, but is more convenient AND more efficient. ::
+
+        e.g.
+        sq> printf("%s %d 0x%02X\n","this is a test :",123,10);
+        this is a test : 123 0x0A
+
 .. js:function:: lstrip(str)
 
     Strips white-space-only characters that might appear at the beginning of the given string