HTMLparser: Correctly initialise a stack allocated structure

If not initialised, the ‘node’ member remains undefined.

Coverity issue: #60466

https://bugzilla.gnome.org/show_bug.cgi?id=731990
xmlcatalog: Fix a memory leak on quit

Coverity issue: #60442

https://bugzilla.gnome.org/show_bug.cgi?id=731990
xmlIO: Fix an FD leak on gzdopen() failure

According to the documentation, gzdopen() does not close the FD on
failure (but does effectively close it on success, since gzclose()
closes it).

Coverity issues: #60440, #60441

https://bugzilla.gnome.org/show_bug.cgi?id=731990
runtest: Fix a memory leak on parse failure

Coverity issue: #60439

https://bugzilla.gnome.org/show_bug.cgi?id=731990
xmlschemastypes: Fix potential array overflow

The year and month need validating before being put into the
MAX_DAYINMONTH macro.

Coverity issue: #60436

https://bugzilla.gnome.org/show_bug.cgi?id=731990
typo in error messages "colon are forbidden from..."

For https://bugzilla.gnome.org/show_bug.cgi?id=731511
Pointed byt vincent Lefevre
Add couple of missing Null checks

For https://bugzilla.gnome.org/show_bug.cgi?id=733710
Reported by Gaurav but with slightly different fixes
Remove a couple of dead conditions

For https://bugzilla.gnome.org/show_bug.cgi?id=733711
Merge branch 'master' of git://git.gnome.org/libxml2 into os400