CRM-14092 - CRM_Utils_Check_Security::isBrowseable - Fix warning

We don't care if there's an HTTP 404 when checking for browsability --
because 404 is another of saying "not browseable!"
Merge pull request #2483 from totten/4.4-security-warning

CRM-14092 - CRM_Utils_Check_Security::isBrowseable - Fix warning
CRM-14179 fix word replacement existing rows count
CRM-14091, CRM-14092 - Defensive programming
Merge pull request #2484 from lcdservices/CRM-14179

CRM-14179 fix word replacement existing rows count
CRM-14091, CRM-14092 - restrictAccess - Avoid unnecessary writes
Merge pull request #2485 from totten/4.4-security-cleanup

CRM-14091, CRM-14092 - More caution
Merge remote-tracking branch 'upstream/4.4' into 4.4-master-2014-02-06-10-43-01