Added all Section 6 items from Levels 1 & 2

https://benchmarks.cisecurity.org/tools2/ubuntu/CIS_Ubuntu_12.04_LTS_Server_Benchmark_v1.0.0.pdf
Added all items from CIS Section 5 Levels 1 & 2
Fixes as requested for PRs

-Fixed typo with section tag
-Added purge to apt removes in this and previous sections
-Updated readme to add warning regarding non-64bit architectures
-Added prelink execution to remove headers if installed
Fixed a typo with section 4.4
Removed extra whitespace
Merge remote-tracking branch 'origin/master' into ubuntu-support-section6

Conflicts:
	tasks/main.yml
	tasks/section_04_level1.yml
Fixed extra white space in section 5 level 1
Updated apt tasks to purge when removing packages
Merge pull request #5 from waveaccounting/ubuntu-support-section6

Added all Section 6 items from Levels 1 & 2
Merge remote-tracking branch 'origin/master' into ubuntu-support-section7

Conflicts:
	tasks/main.yml