RFR: 8260328: Drop redundant CSS properties from java.desktop HTML files

[Alexey Ivanov]

Drop redundant `text-align: left` from `<table>` elements, which don't affect the table alignment. Then drop `text-align: center` from `<th> elements which counter-act the align set on the `<table>`.

Also drop `vertical-align: top` from table cells and declare this style globally. This makes the properties and values be rendered at the top of the table cell in cases where the description wraps to multiple lines.

Visually, the updated tables look nearly the same way as before. I left out applying top alignment for `<thead>` elements: the headers are center-aligned. You can see this in tables for `JOptionPane`, `JProgressBar` and other components which have long descriptions so that *Expected Type* and *Default Value* are wrapped to two lines.

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Commit messages:
 - 8260328: Drop more 'vertical-align: top' from elements
 - 8260328: Drop 'vertical-align: top' from elements

Changes: https://git.openjdk.java.net/jdk/pull/7546/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=7546&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8260328
  Stats: 180 lines in 1 file changed: 3 ins; 0 del; 177 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7546.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7546/head:pull/7546

PR: https://git.openjdk.java.net/jdk/pull/7546