docs/config: clarify include/includeIf relationship

The "includeIf" directives behave exactly like include ones,
except they only kick in when the conditional is true. That
was mentioned in the "conditional" section, but let's make
it more clear for the whole "includes" section, since people
don't necessarily read the documentation top to bottom.

Signed-off-by: Jeff King <[email protected]>
Reviewed-by: Ævar Arnfjörð Bjarmason <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: peff

Documentation/config.txt

@@ -79,14 +79,20 @@ escape sequences) are invalid.
 Includes
 ~~~~~~~~
 
+The `include` and `includeIf` sections allow you to include config
+directives from another source. These sections behave identically to
+each other with the exception that `includeIf` sections may be ignored
+if their condition does not evaluate to true; see "Conditional includes"
+below.
+
 You can include a config file from another by setting the special
-`include.path` variable to the name of the file to be included. The
-variable takes a pathname as its value, and is subject to tilde
-expansion. `include.path` can be given multiple times.
+`include.path` (or `includeIf.*.path`) variable to the name of the file
+to be included. The variable takes a pathname as its value, and is
+subject to tilde expansion. These variables can be given multiple times.
 
 The included file is expanded immediately, as if its contents had been
 found at the location of the include directive. If the value of the
-`include.path` variable is a relative path, the path is considered to
+variable is a relative path, the path is considered to
 be relative to the configuration file in which the include directive
 was found.  See below for examples.
 
@@ -95,8 +101,7 @@ Conditional includes
 
 You can include a config file from another conditionally by setting a
 `includeIf.<condition>.path` variable to the name of the file to be
-included. The variable's value is treated the same way as
-`include.path`. `includeIf.<condition>.path` can be given multiple times.
+included.
 
 The condition starts with a keyword followed by a colon and some data
 whose format and meaning depends on the keyword. Supported keywords