more code review comments

Author: siretart

common/docs/containerignore.5.md

@@ -36,37 +36,41 @@ temp?
 ```
 
 This file causes the following build behavior:
-Rule 	Behavior
 
-```
-# comment 	Ignored.
-*/temp* 	Exclude files and directories whose names start with temp in any immediate subdirectory of the root.
-For example, the plain file /somedir/temporary.txt is excluded, as is the directory /somedir/temp.
-*/*/temp* 	Exclude files and directories starting with temp from any subdirectory that is two levels below the
-root. For example, /somedir/subdir/temporary.txt is excluded.
-temp? 	Exclude files and directories in the root directory whose names are a one-character extension of temp. For example, /tempa and /tempb are excluded.
-```
+`#comment`: Lines that start with the `#` character are ignored.
+
+`*/temp*`: Exclude files and directories whose names start with temp in any
+immediate subdirectory of the root.  For example, the plain file
+/somedir/temporary.txt is excluded, as is the directory /somedir/temp.
+
+`*/*/temp*`: Exclude files and directories starting with temp from any
+subdirectory that is two levels below the root. For example,
+/somedir/subdir/temporary.txt is excluded.
 
-Matching is done using the golang `path/filepath` package.
+`temp?`: Exclude files and directories in the root directory whose names are a
+one-character extension of temp. For example, /tempa and /tempb are excluded.
 
-Match rules:
- * A preprocessing step removes leading and trailing whitespace and eliminates
-   . and .. elements using the golang `path/filepath` package.
- * Lines that are blank after preprocessing are ignored.
+
+Matching is done using the `filepath.Match` rules:
+
+* A preprocessing step removes leading and trailing whitespace and eliminates
+  . and .. elements using the golang `path/filepath` package.
+* Lines that are blank after preprocessing are ignored.
 
 Beyond the `filepath.Match` rules, Docker also supports a special wildcard
 string `**` that matches any number of directories (including zero). For
 example, `**/*.go` will exclude all files that end with `.go` that are found in
 all directories, including the root of the build context.
 
 Lines starting with `!` (exclamation mark) can be used to make exceptions to
-exclusions. The following is an example .containerignore file that uses this
+exclusions. The following is an example `.containerignore` file that uses this
 mechanism:
 
 ```
 *.md
 !README.md
 ```
+
 All markdown files except README.md are excluded from the context.
 
 The placement of `!` exception rules influences the behavior: the last line of
@@ -78,7 +82,8 @@ included or excluded. Consider the following example:
 !README*.md
 README-secret.md
 ```
-No markdown files are included in the context except README files other than README-secret.md.
+
+No markdown files are included in the context except `README` files other than `README-secret.md`.
 
 Now consider this example:
 
@@ -104,4 +109,4 @@ followed by one or more `!` exception patterns.
 buildah-build(1), podman-build(1), docker-build(1)
 
 # HISTORY
-*Sep 2021, Compiled by Dan Walsh (dwalsh at redhat dot com) based on docker.com .dockerignore documentation.
+*Sep 2021, Compiled by Dan Walsh (dwalsh at redhat dot com) based on docker.com `.dockerignore` documentation.