pginstaller - pginst: * Change "Install as a service" to be a checkbox

Log Message:
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* Change "Install as a service" to be a checkbox to be the same as initdb.

* Fix bug that showed if you enabled server install, enabled service, then went back and disbaled server. Would call
wrongcustom actions. 

Modified Files:
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    pginst/wxs:
        dialogs.wxs (r1.7 -> r1.8)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pginstaller/pginst/wxs/dialogs.wxs.diff?r1=1.7&r2=1.8)
        pginst.wxs (r1.13 -> r1.14)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pginstaller/pginst/wxs/pginst.wxs.diff?r1=1.13&r2=1.14)