Add profiling and POST size stats

Enable collector profiling by adding profile: yes in `datadog.conf`
Re-introduce raise statement that was removed by mistake
Fix per pull request comments
Ignore Vagrant
Simple cosmetic logging fix
haproxy - Calculate used session percentage

Calculate the percentage of used sessions (spct) from the current number of sessions (scur) and the session limit (slim).
haproxy - Catch divide by zero
Don't puke on archives

raise `Skip` and continue on cleanly when coming 
across jobs that have builds which have 
been tar'd up.
Merge branch 'master' into profiler

Conflicts:
	checks/ganglia.py
Merge branch 'master' into profiler
include tags so we can search at the metric/check level rather than just at host level
add url to tag list
Add EC2 tags to other system tags, to prevent them from overwriting other AWS tags.
java_options config param was added
Make collection of ec2 tags configurable.  Return empty tag list in case of error.
Merge pull request #774 from ive/JAVA_OPT

Allow java options in path_to_java
Merge pull request #780 from bakins/include-tags

Include tags with http service check
Merge branch 'master' into profiler

Conflicts:
	.gitignore
	Vagrantfile
	packaging/datadog-agent-deb/postinst
	packaging/datadog-agent-rpm/preinst
Code review feedback:
-Move config value handling to config.py
-Remove EC2 SourceTypeId
-Log EC2 tag retrieval exceptions
Merge pull request #789 from DataDog/agent_aws_tags_to_system

Agent aws tags to system