Add note about case sensitivity for Little Women challenge (#984)

Fix #932.

_episodes/07-find.md

@@ -18,8 +18,8 @@ keypoints:
 - "`$(command)` inserts a command's output in place."
 ---
 
-In the same way that many of us now use "Google" as a 
-verb meaning "to find", Unix programmers often use the 
+In the same way that many of us now use "Google" as a
+verb meaning "to find", Unix programmers often use the
 word "grep".
 "grep" is a contraction of "global/regular expression/print",
 a common sequence of operations in early Unix text editors.
@@ -114,7 +114,7 @@ The Tao that is seen
 {: .output}
 
 Note that a "word boundary" includes the start and end of a line, so not
-just letters surrounded by spaces. 
+just letters surrounded by spaces.
 Sometimes we don't
 want to search for a single word, but a phrase. This is also easy to do with
 `grep` by putting the phrase in quotes.
@@ -282,10 +282,10 @@ Miscellaneous:
 {: .callout}
 
 > ## Tracking a Species
-> 
-> Leah has several hundred 
+>
+> Leah has several hundred
 > data files saved in one directory, each of which is formatted like this:
-> 
+>
 > ~~~
 > 2013-11-05,deer,5
 > 2013-11-05,rabbit,22
@@ -295,27 +295,27 @@ Miscellaneous:
 > ~~~
 > {: .source}
 >
-> She wants to write a shell script that takes a species as the first command-line argument 
-> and a directory as the second argument. The script should return one file called `species.txt` 
+> She wants to write a shell script that takes a species as the first command-line argument
+> and a directory as the second argument. The script should return one file called `species.txt`
 > containing a list of dates and the number of that species seen on each date.
 > For example using the data shown above, `rabbit.txt` would contain:
-> 
+>
 > ~~~
 > 2013-11-05,22
 > 2013-11-06,19
 > ~~~
 > {: .source}
 >
 > Put these commands and pipes in the right order to achieve this:
-> 
+>
 > ~~~
-> cut -d : -f 2  
-> >  
-> |  
-> grep -w $1 -r $2  
-> |  
-> $1.txt  
-> cut -d , -f 1,3  
+> cut -d : -f 2
+> >
+> |
+> grep -w $1 -r $2
+> |
+> $1.txt
+> cut -d , -f 1,3
 > ~~~
 > {: .language-bash}
 >
@@ -381,6 +381,11 @@ Miscellaneous:
 > > This solution is inferior because `grep -c` only reports the number of lines matched.
 > > The total number of matches reported by this method will be lower if there is more
 > > than one match per line.
+> >
+> > Perceptive observers may have noticed that character names sometimes appear in all-uppercase
+> > in chapter titles (e.g. "MEG GOES TO VANITY FAIR").
+> > If you wanted to count these as well, you could add the `-i` option for case-insensitivity
+> > (though in this case, it doesn't affect the answer to which sister is mentioned most frequently).
 > {: .solution}
 {: .challenge}
 
@@ -429,7 +434,7 @@ which is where we want our search to start.
 `find`'s output is the names of every file **and** directory
 under the current working directory.
 This can seem useless at first but `find` has many options
-to filter the output and in this lesson we will discover some 
+to filter the output and in this lesson we will discover some
 of them.
 
 The first option in our list is
@@ -656,7 +661,7 @@ about them."
 {: .challenge}
 
 > ## Finding Files With Different Properties
-> 
+>
 > The `find` command can be given several other criteria known as "tests"
 > to locate files with specific attributes, such as creation time, size,
 > permissions, or ownership.  Use `man find` to explore these, and then