Fix missing close paren. Thanks to Jurko Gospodnetić for spotting the typo.

[SVN r42302]

historic/jam/doc/bjam.qbk

@@ -1773,7 +1773,7 @@ This section is derived from the official Jam documentation and from experience
 * "Grist" is just a string prefix of the form </characters/>. It is used in Jam to create unique target names based on simpler names. For example, the file name "=test.exe=" may be used by targets in separate subprojects, or for the debug and release variants of the "same" abstract target. Each distinct target bound to a file called "test.exe" has its own unique grist prefix. The Boost build system also takes full advantage of Jam's ability to divide strings on grist boundaries, sometimes concatenating multiple gristed elements at the beginning of a string. Grist is used instead of identifying targets with absolute paths for two reasons:
 
    # The location of targets cannot always be derived solely from what the user puts in a Jamfile, but sometimes depends also on the binding process. Some mechanism to distinctly identify targets with the same name is still needed.
-   # Grist allows us to use a uniform abstract identifier for each built target, regardless of target file location (as allowed by setting ALL_LOCATE_TARGET.
+   # Grist allows us to use a uniform abstract identifier for each built target, regardless of target file location (as allowed by setting ALL_LOCATE_TARGET).
 
 * When grist is extracted from a name with $(var:G), the result includes the leading and trailing angle brackets. When grist is added to a name with $(var:G=expr), existing grist is first stripped. Then, if expr is non-empty, leading <s and trailing >s are added if necessary to form an expression of the form <expr2>; <expr2> is then prepended.