Fix all pylint errors except TODOs
Make exceptions moved to xblock.exceptions still available in xblock.core
Merge pull request #260 from cpennington/clean-up-pylint

Fix all pylint errors except TODOs
Merge pull request #259 from cpennington/backcompat-exceptions

Make exceptions moved to xblock.exceptions still available in xblock.core
Pull XML serialization out into a separate mixin [PLAT-229]
Make the number of pylint violations a default value in the script, overrideable elsewhere
Fix script/coverage
Add a pre-push hook that can be used to validate pylint and pep8 values
Add methods to IdReader and IdGenerator for working with XBlockAside usage ids [PLAT-210]
Make base abstract methods raise NotImplementedError
Ignore common non-coverable lines
Merge pull request #264 from cpennington/default-pre-pylint-number

Make violation checking a little more automatic
Merge pull request #265 from cpennington/fix-coverage-script

Fix script/coverage
Merge pull request #263 from cpennington/separate-xml-serialization-mixin

Pull XML serialization out into a separate mixin [PLAT-229]
Merge pull request #262 from cpennington/xblock-aside-ids

Add methods to IdReader and IdGenerator for working with XBlockAside usage ids [PLAT-210]
Provide a method for Runtimes to instantiate the Asides for a block
Associate aside view handlers with xblock view they decorate

[PLAT-233]