stop validating dtd for comments generation

[robe]

I am so tired of gettting build bot failures everytime dtd validation checks fail. This often happens because of network failures downloading dtd.

I propose we change the comments generation sections to the form

postgis_comments.sql: ./xsl/postgis_comments.sql.xsl $(XML_INPUTS)
	$(XSLTPROC) --novalid ./xsl/postgis_comments.sql.xsl postgis-out.xml > $@

[robe]

Well this is mighty annoying, it appears I need validation for raster because of the use of pi in:

​http://www.postgis.org/documentation/manual-svn/RT_ST_Aspect.html

Can we do without the pi symbol or maybe locally define it in postgis.xml

without that I get a parse error on use of π

[Bborie Park]

Oh wow. Completely forgot I'm using the actual pi character. I'll remove that...

[Bborie Park]

And the actual pi character is only found in -trunk, not 2.0.

[Bborie Park]

I've removed the use of the html code for pi in r10772.

[robe]

yah 2.0 didn't seem to give me issue when I changed to --no-valid. I hard-coded on winnie to see if it helps her stop whining a bit. i'll try that next for 2.1 after I retest.

[robe]

Done for 2.1 at r10775

[robe]

Done for 2.0 at r10794