DOC: config: indent the list of environment variables

In the doc our lists are indented but for any reason this one was not,
making it harder to visually delimit. Let's just indent it. No need to
backport this, it's totally cosmetic and would need adaptations since
it was recently touched.

Author: wtarreau

doc/configuration.txt

@@ -1007,64 +1007,64 @@ modes:
 
 The variables in question are the following:
 
-* HAPROXY_LOCALPEER: defined at the startup of the process which contains the
-  name of the local peer. (See "-L" in the management guide.)
+  * HAPROXY_LOCALPEER: defined at the startup of the process which contains the
+    name of the local peer. (See "-L" in the management guide.)
 
-* HAPROXY_CFGFILES: list of the configuration files loaded by HAProxy,
-  separated by semicolons. Can be useful in the case you specified a
-  directory.
+  * HAPROXY_CFGFILES: list of the configuration files loaded by HAProxy,
+    separated by semicolons. Can be useful in the case you specified a
+    directory.
 
-* HAPROXY_HTTP_LOG_FMT: contains the value of the default HTTP log format as
-  defined in section 8.2.3 "HTTP log format". It can be used to override the
-  default log format without having to copy the whole original definition.
+  * HAPROXY_HTTP_LOG_FMT: contains the value of the default HTTP log format as
+    defined in section 8.2.3 "HTTP log format". It can be used to override the
+    default log format without having to copy the whole original definition.
 
-* HAPROXY_HTTP_CLF_LOG_FMT: contains the value of the default HTTP CLF log
-  format as defined in section 8.2.3 "HTTP log format". It can be used to
-  override the default log format without having to copy the whole original
-  definition.
+  * HAPROXY_HTTP_CLF_LOG_FMT: contains the value of the default HTTP CLF log
+    format as defined in section 8.2.3 "HTTP log format". It can be used to
+    override the default log format without having to copy the whole original
+    definition.
 
-  Example:
-    # Add the rule that gave the final verdict to the log
-    log-format "${HAPROXY_TCP_LOG_FMT} lr=last_rule_file:last_rule_line"
+    Example:
+      # Add the rule that gave the final verdict to the log
+      log-format "${HAPROXY_TCP_LOG_FMT} lr=last_rule_file:last_rule_line"
 
-* HAPROXY_HTTPS_LOG_FMT: similar to HAPROXY_HTTP_LOG_FMT but for HTTPS log
-  format as defined in section 8.2.4 "HTTPS log format".
+  * HAPROXY_HTTPS_LOG_FMT: similar to HAPROXY_HTTP_LOG_FMT but for HTTPS log
+    format as defined in section 8.2.4 "HTTPS log format".
 
-* HAPROXY_TCP_LOG_FMT: similar to HAPROXY_HTTP_LOG_FMT but for TCP log format
-  as defined in section 8.2.2 "TCP log format".
+  * HAPROXY_TCP_LOG_FMT: similar to HAPROXY_HTTP_LOG_FMT but for TCP log format
+    as defined in section 8.2.2 "TCP log format".
 
-* HAPROXY_TCP_CLF_LOG_FMT: similar to HAPROXY_HTTP_CLF_LOG_FMT but for TCP CLF
-  log format as defined in section 8.2.2 "TCP log format".
+  * HAPROXY_TCP_CLF_LOG_FMT: similar to HAPROXY_HTTP_CLF_LOG_FMT but for TCP
+    CLF log format as defined in section 8.2.2 "TCP log format".
 
-* HAPROXY_MWORKER: In master-worker mode, this variable is set to 1.
+  * HAPROXY_MWORKER: In master-worker mode, this variable is set to 1.
 
-* HAPROXY_CLI: configured listeners addresses of the stats socket of every
-  processe, these addresses are separated by semicolons.
+  * HAPROXY_CLI: configured listeners addresses of the stats socket of every
+    processe, these addresses are separated by semicolons.
 
-* HAPROXY_MASTER_CLI: In master-worker mode, listeners addresses of the master
-  CLI, separated by semicolons.
+  * HAPROXY_MASTER_CLI: In master-worker mode, listeners addresses of the master
+    CLI, separated by semicolons.
 
-* HAPROXY_STARTUP_VERSION: contains the version used to start, in master-worker
-  mode this is the version which was used to start the master, even after
-  updating the binary and reloading.
+  * HAPROXY_STARTUP_VERSION: contains the version used to start, in master-
+    worker mode this is the version which was used to start the master, even
+    after updating the binary and reloading.
 
-* HAPROXY_BRANCH: contains the HAProxy branch version (such as "2.8"). It does
-  not contain the full version number. It can be useful in case of migration
-  if resources (such as maps or certificates) are in a path containing the
-  branch number.
+  * HAPROXY_BRANCH: contains the HAProxy branch version (such as "2.8"). It
+    does not contain the full version number. It can be useful in case of
+    migration if resources (such as maps or certificates) are in a path
+    containing the branch number.
 
 In addition, some pseudo-variables are internally resolved and may be used as
 regular variables. Pseudo-variables always start with a dot ('.'), and are the
 only ones where the dot is permitted. The current list of pseudo-variables is:
 
-* .FILE: the name of the configuration file currently being parsed.
+  * .FILE: the name of the configuration file currently being parsed.
 
-* .LINE: the line number of the configuration file currently being parsed,
-  starting at one.
+  * .LINE: the line number of the configuration file currently being parsed,
+    starting at one.
 
-* .SECTION: the name of the section currently being parsed, or its type if the
-  section doesn't have a name (e.g. "global"), or an empty string before the
-  first section.
+  * .SECTION: the name of the section currently being parsed, or its type if
+    the section doesn't have a name (e.g. "global"), or an empty string before
+    the first section.
 
 These variables are resolved at the location where they are parsed. For example
 if a ".LINE" variable is used in a "log-format" directive located in a defaults