rename tabs

this addresses issue #77. i also removed the alpha rarefaction tab, and will put that information in a new section on the alpha diversity boxplots page.
adding back alpha rarefaction plots

linked under an 'advanced' section in alpha diversity boxplots.
Added option to use existing rarefied/split tables
Merge branch 'master' into issue_75

Conflicts:
	my_microbes/util.py
	scripts/personal_results.py
worked on text for alpha diversity

this addresses #70. #77 was addressed in previous commit, but forgot to note the issue number.
Merge branch 'master' into text-updates
Merge pull request #85 from jrrideout/issue_75

Added option to use existing rarefied/split tables.
fixed two typos
Merge pull request #87 from gregcaporaso/text-updates

Text updates