cgitrc.5.txt: reformat the "FILTER API" section

This patch makes the generated man-page for the filer api section more
similar to the other sections. Also, the bulleted list of environment
variables wasn't rendered correctly (with asciidoc 8.5.2), without an
empty line before the first item.

Signed-off-by: Lars Hjemli <hjemli@gmail.com>

cgitrc.5.txt

@@ -460,39 +460,37 @@ config files, e.g. "repo.desc" becomes "desc".
 
 FILTER API
 ----------
-- about filter::
+about filter::
-  This filter is given no arguments.
+	This filter is given no arguments. The about text that is to be
-  The about text that is to be filtered is available on standard input and the
+	filtered is available on standard input and the filtered text is
-  filtered text is expected on standard output.
+	expected on standard output.
-- commit filter::
+
-  This filter is given no arguments.
+commit filter::
-  The commit message text that is to be filtered is available on standard input
+	This filter is given no arguments. The commit message text that is to
-  and the filtered text is expected on standard output.
+	be filtered is available on standard input and the filtered text is
-- source filter::
+	expected on standard output.
-  This filter is given a single parameter: the filename of the source file to
+
-  filter. The filter can use the filename to determine (for example) the syntax
+source filter::
-  highlighting mode.
+	This filter is given a single parameter: the filename of the source
-  The contents of the source file that is to be filtered is available on
+	file to filter. The filter can use the filename to determine (for
-  standard input and the filtered contents is expected on standard output.
+	example) the syntax highlighting mode. The contents of the source
+	file that is to be filtered is available on standard input and the
+	filtered contents is expected on standard output.
 
 Also, all filters are handed the following environment variables:
-- CGIT_REPO_URL        ( = repo.url       setting )
+
-- CGIT_REPO_NAME       ( = repo.name      setting )
+- CGIT_REPO_URL (from repo.url)
-- CGIT_REPO_PATH       ( = repo.path      setting )
+- CGIT_REPO_NAME (from repo.name)
-- CGIT_REPO_OWNER      ( = repo.owner     setting )
+- CGIT_REPO_PATH (from repo.path)
-- CGIT_REPO_DEFBRANCH  ( = repo.defbranch setting )
+- CGIT_REPO_OWNER (from repo.owner)
-- CGIT_REPO_SECTION    ( = section        setting )
+- CGIT_REPO_DEFBRANCH (from repo.defbranch)
-- CGIT_REPO_CLONE_URL  ( = repo.clone-url setting )
+- CGIT_REPO_SECTION (from repo.section)
+- CGIT_REPO_CLONE_URL (from repo.clone-url)
 
 If a setting is not defined for a repository and the corresponding global
 setting is also not defined (if applicable), then the corresponding
 environment variable will be an empty string.
 
-Note that under normal circumstance all these environment variables are
-defined. If however the total size of the defined settings exceed the
-allocated buffer within cgit then only the environment variables that fit
-in the allocated buffer are handed to the filter.
-
 
 MACRO EXPANSION
 ---------------