8016217: More javadoc warnings

[Alan Bateman]

About 8 months ago I tried an early build of doclint [1] and used it to 
fix up a bunch issues at the time [2]. It's been awhile, so I decided to 
try out the latest version to see how it has progressed. All I can say 
is "Yikes".  The good news is that they reported against the original 
source and that makes it easy when compared to tools that validate the 
generated html.

I decided to fix up a few issues, mostly syntax (escaping of > and < in 
particular) and a few reference issues that were missed the last time 
(or are new). There are thousands of other issues for anyone that wants 
to jump in.

I've put the webrev with the changes here:

http://cr.openjdk.java.net/~alanb/8016217/webrev/

In total this fixes ~500 issues, although 270 of those were coming from 
java.sql.DatabaseMetaData due to the number of un-escaped usages of  
"=>". In many cases, the changes are simply to use {@code ..} or replace 
<code> with {@code ...}. It is tempting to just do a global replace on 
existing <code></code> usages (would fixing up content that is escaped 
of course).

I've run specdiff on the before & after to check that I didn't mess 
anything up. One obvious difference is that code examples that use 
generics now have the type parameters going through to the generated 
javadoc.

The webrev touches many areas but as the changes are trivial, I don't 
need a reviewer from every area.

-Alan.

[1] http://openjdk.java.net/jeps/172
[2] http://hg.openjdk.java.net/jdk8/tl/jdk/rev/39cbe256c3d1