Fix doc typos.

Signed-off-by: Ralf Wildenhues <Ralf.Wildenhues@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-grep.txt

@@ -78,7 +78,7 @@ OPTIONS
 -l | --files-with-matches | --name-only | -L | --files-without-match::
 	Instead of showing every matched line, show only the
 	names of files that contain (or do not contain) matches.
-	For better compatability with git-diff, --name-only is a
+	For better compatibility with git-diff, --name-only is a
 	synonym for --files-with-matches.
 
 -c | --count::

Documentation/technical/api-run-command.txt

@@ -49,7 +49,7 @@ Functions
 
 `finish_async`::
 
-	Wait for the completeion of an asynchronous function that was
+	Wait for the completion of an asynchronous function that was
 	started with start_async().
 
 
@@ -121,8 +121,8 @@ string pointers (NULL terminated) in .env:
 . If the string is of the form "VAR=value", i.e. it contains '='
   the variable is added to the child process's environment.
 
-. If the string does not contain '=', it names an environement
-  variable that will be removed from the child process's envionment.
+. If the string does not contain '=', it names an environment
+  variable that will be removed from the child process's environment.
 
 To specify a new initial working directory for the sub-process,
 specify it in the .dir member.