Added pop and fixed issue with triple quoted strings

#118 and #120

Implemented contains method and fixed bug where last line is a comment

0.3.35

bumped version to 0.3.35

Fixed error handling that was unable to deal with unicode keys and Python 2.6 incompatible format string

0.3.34

bumped version to 0.3.34

fixed include

0.3.32

flake8 fix

Bug fix for variables that start with include-blabla

0.3.31

bumped version

Bug fix for ConfigTree.get_bool()

0.3.30

Bumped version to 0.3.30

Don't lock pyparsing to a specific version

0.3.29

bumped version

Fixed quoted string

0.3.28

bumped version

Fixes for self-reference resolution after merging configs and key with dots

0.3.27

bumped version

self reference substitutions and +=

0.3.26

updated CHANGELOG and version