Merge pull request #181 from qboss/master

A couple of pages converted to markdown.
Moved the '$' in shell command code helper to css.

Triple clicking on shell command currently selects the '$' which is only
there to denote command prompt. Shell commands are still prefixed with the
same '$' but it is done using a :before pseudo-class in css.
Merge pull request #182 from harith/master

Moved the '$' in shell command code helper to css.
CSS fix for ignored space after command prompt

Firefox ignores the whitespace in 'content' attribute of pseudo
elements. Replaced the whitespace with '\00a0'

ref: https://developer.mozilla.org/en-US/docs/Web/CSS/content
Merge pull request #183 from harith/master

CSS fix for ignored space after command prompt
new webfont for better readability

added a google font 'Open sans' for better readability.
Merge pull request #184 from lixonic/patch-1

new webfont for better readability
Bring up the introduction to top
Merge pull request #187 from lixonic/patch-3

Bring up the introduction to top
clarify installation flags on the ain page
Adding sudo integration points
Updating with vars needed by Capistrano's RVM integration
Merge pull request #189 from sardaukar/master

Adding sudo integration points
add a link to sudo wiki, add a note about adding more variables to env_keep, update #189
Fix 'gemset' typo.
Merge pull request #190 from nbibler/patch-1

Fix 'gemset' typo in Cron documentation
remove instructions to run requirements, it is run during installation
Merge branch 'master' of github.com:rvm/rvm-site
reworked project files descriptions, closes #191
add automatic links for headers