heyho, PyX weekend is about to start; fix layered canvas args

git-svn-id: https://pyx.svn.sourceforge.net/svnroot/pyx/trunk/pyx@3248 069f4177-920e-0410-937b-c2a4a81bcd90
a simple test of the layer functionality

git-svn-id: https://pyx.svn.sourceforge.net/svnroot/pyx/trunk/pyx@3249 069f4177-920e-0410-937b-c2a4a81bcd90
canvas.insert now returns canvas wrapping item if attrs are given

git-svn-id: https://pyx.svn.sourceforge.net/svnroot/pyx/trunk/pyx@3250 069f4177-920e-0410-937b-c2a4a81bcd90
canvas.insert allows specification of position where item is inserted by before and after arguments

git-svn-id: https://pyx.svn.sourceforge.net/svnroot/pyx/trunk/pyx@3251 069f4177-920e-0410-937b-c2a4a81bcd90
support inserting of layers above and below other ones

git-svn-id: https://pyx.svn.sourceforge.net/svnroot/pyx/trunk/pyx@3252 069f4177-920e-0410-937b-c2a4a81bcd90
remove spurious TODOs

git-svn-id: https://pyx.svn.sourceforge.net/svnroot/pyx/trunk/pyx@3253 069f4177-920e-0410-937b-c2a4a81bcd90
remove spurious TODOs

git-svn-id: https://pyx.svn.sourceforge.net/svnroot/pyx/trunk/pyx@3254 069f4177-920e-0410-937b-c2a4a81bcd90
revert changeset 3223 (explanation required, breaks functional test, ...)

git-svn-id: https://pyx.svn.sourceforge.net/svnroot/pyx/trunk/pyx@3255 069f4177-920e-0410-937b-c2a4a81bcd90
- merge _canvas, canvas and layered_canvas
- writeXXXfile methods now use "page_" and "write_" prefixes for passing
  the keyword arguments to the page constructor and write method
- fix CHANGES entry


git-svn-id: https://pyx.svn.sourceforge.net/svnroot/pyx/trunk/pyx@3256 069f4177-920e-0410-937b-c2a4a81bcd90
missing checkin

git-svn-id: https://pyx.svn.sourceforge.net/svnroot/pyx/trunk/pyx@3257 069f4177-920e-0410-937b-c2a4a81bcd90
fix backspace notation

git-svn-id: https://pyx.svn.sourceforge.net/svnroot/pyx/trunk/pyx@3258 069f4177-920e-0410-937b-c2a4a81bcd90
pass proper kwargs to page constructor and write method

git-svn-id: https://pyx.svn.sourceforge.net/svnroot/pyx/trunk/pyx@3259 069f4177-920e-0410-937b-c2a4a81bcd90
fix typos

git-svn-id: https://pyx.svn.sourceforge.net/svnroot/pyx/trunk/pyx@3260 069f4177-920e-0410-937b-c2a4a81bcd90
graph density style example (based on the mandel gallery example)

git-svn-id: https://pyx.svn.sourceforge.net/svnroot/pyx/trunk/pyx@3261 069f4177-920e-0410-937b-c2a4a81bcd90
rename bitmap style to density style

git-svn-id: https://pyx.svn.sourceforge.net/svnroot/pyx/trunk/pyx@3262 069f4177-920e-0410-937b-c2a4a81bcd90
fix description

git-svn-id: https://pyx.svn.sourceforge.net/svnroot/pyx/trunk/pyx@3263 069f4177-920e-0410-937b-c2a4a81bcd90
add ASCIIHexDecode end marker

git-svn-id: https://pyx.svn.sourceforge.net/svnroot/pyx/trunk/pyx@3264 069f4177-920e-0410-937b-c2a4a81bcd90
add CHANGES note for rev 3264

git-svn-id: https://pyx.svn.sourceforge.net/svnroot/pyx/trunk/pyx@3265 069f4177-920e-0410-937b-c2a4a81bcd90
graph uses new canvas layers to stack its components (fixing bug #1518414, reported by Dominic Ford)


git-svn-id: https://pyx.svn.sourceforge.net/svnroot/pyx/trunk/pyx@3266 069f4177-920e-0410-937b-c2a4a81bcd90
add popen2 functionality in pycompat module

git-svn-id: https://pyx.svn.sourceforge.net/svnroot/pyx/trunk/pyx@3267 069f4177-920e-0410-937b-c2a4a81bcd90