Wrap search pattern in non-capturing group

If you have a search pattern with an alternation in it (ex.
\<foo\|bar\>), the pattern fed to match is interpreted as "match
this column/line combo plus the first branch OR the second branch",
resulting in multiple things flashing in the buffer.  This patch
wraps the whole search string in a non-capturing group to prevent
this behavior
Merge pull request #9 from hoelzro/master

Wrap search pattern in non-capturing group