Recketizing much in `net/*', mass ".ss" -> ".rkt" conversion in .scrbl files.

(Some other minor things here and there.)

original commit: debd1f9f1e6899e2a7e4ab5de929a49df490b5c7

collects/profile/scribblings/analyzer.scrbl

@@ -51,7 +51,7 @@ Represents the analyzed profile result.
 @item{@scheme[thread-times] holds an association list mapping thread
   identifiers to cpu time for the corresponding threads.  As samples
   are collected, each thread that is observed is assigned a small
-  integer identifier.  These identifers are listed for each function
+  integer identifier.  These identifiers are listed for each function
   call, and the total time spent in each thread is in this field.}
 
 @item{@scheme[nodes] is a list of nodes representing all observed
@@ -65,7 +65,7 @@ Represents the analyzed profile result.
   constructed for every graph.  This node is used as the caller for
   all top-level function nodes and as the callee for all leaf nodes.
   It can therefore be used to start a scan of the call graph.  In
-  addition, the times associated with it's "callers and callees"
+  addition, the times associated with its "callers and callees"
   actually represent the time these functions spent being the root of
   the computation or its leaf.  (This can be different from a node's
   ``self'' time, since it is divided by the number of instances a

collects/profile/scribblings/renderers.scrbl

@@ -35,7 +35,7 @@ this table looks like:
 
 @verbatim[#:indent 2]{
                           B [M1] M2%
-  [N1] N2(N3%) N4(N5%)  A ...path/to/source.ss:12:34
+  [N1] N2(N3%) N4(N5%)  A ...path/to/source.rkt:12:34
                           C [M3] M4%}
 
 Where actual numbers appear in the printout.  The meaning of the

collects/profile/scribblings/toplevel.scrbl

@@ -9,7 +9,7 @@
 
 @defmodule[profile]
 
-This module provides one procedure and one macroxs that are convenient
+This module provides one procedure and one macro that are convenient
 high-level entry points for timing expressions.  This hides the
 details that are available through other parts of the library, and is
 intended as a convenient tool for profiling code.