Add ATA PIO IRQ handler, documentation

Still WIP, doesn't look like IRQ handler works yet.
diff --git a/doc/kernel.doxyfile b/doc/kernel.doxyfile
index d75e0a8..5d5f1e1 100644
--- a/doc/kernel.doxyfile
+++ b/doc/kernel.doxyfile
@@ -467,7 +467,7 @@
 # normally produced when WARNINGS is set to YES.
 # The default value is: NO.
 
-EXTRACT_ALL            = NO
+EXTRACT_ALL            = YES
 
 # If the EXTRACT_PRIVATE tag is set to YES, all private members of a class will
 # be included in the documentation.
@@ -862,7 +862,7 @@
 # be searched for input files as well.
 # The default value is: NO.
 
-RECURSIVE              = NO
+RECURSIVE              = YES
 
 # The EXCLUDE tag can be used to specify files and/or directories that should be
 # excluded from the INPUT source files. This way you can easily exclude a