Fix for url loading of images in ofImage::loadImage

Re discussion in #3304, ofImage::loadImage did not work on https.
Switched from using a substring check for "http" in the filename to
using Poco::URI to detect http or https in the scheme.
Updaing changelog
"Bug fix" for regex example

The order of attributes on the table tag in the HTML returned from
google has changed slightly.  width now comes before style.  Tested
in 0.8.4 and in master on win codeblocks 12.11.
update PG to latest commit
As per @kylemcdonald's suggestion, regex is attribute order-independent
Merge pull request #3310 from mikewesthad/bug-fix-regex-example

"Bug fix" for regex example
Merge pull request #3308 from mikewesthad/bugfix-loadImage-HTTPS

Fix for url loading of images in ofImage::loadImage
Add printf format checking to printf-style log constructors.

This improves safety by diagnosing format string mismatches under both Clang and GCC.
getPixelsRef -> getPixels

getPixelsRef() is a confusing method name and most beginners keep
using getPixels missing the additional functionality in ofPixels.

this deprecates all getPixelsRef methods and converts all:

```cpp
unsigned char * getPixels();
```

into

```cpp
ofPixels & getPixels();
const ofPixels & getPixels();
```

we might even want to remove the non-const version since it doesn't
really make sense to modify the internal pixels.

also adds a cast operator to unsigned char* to ofPixels so we don't break
any code except for the implementations of ofBaseVideo that will need
to change getPîxelsRef -> getPixels and remove the old method returning
unsigned char*
ofEvents: add constructors to event args. Closes #3312
Merge branch 'master' of github.com:openframeworks/openFrameworks
fix some warnings
examples: remove use of unsigned char * gePixels() for ofPixels & getPixels()
Merge pull request #3311 from nneonneo/printf_patch

Add printf format checking to printf-style log constructors.
gl: fix GLES for new unssuported calls
Merge branch 'master' of github.com:openframeworks/openFrameworks
android: fix getPixelsRef -> getPixels
Merge branch 'master' into refactor-getPixelsRef
ofxOpenCv: getPixelsRef -> getPixels
ofxAndroid, Emscripten and Kinect: getPixelsRef -> getPixels