Remove old info from gitfs top-level docstring

The warning no longer applies since auth support was added for pygit2.

Also added a link to the gitfs walkthrough.
Grammar correction
Fix sphinx build error

There is no 'math' lexer in sphinx.
Fix misspelled code-block type
Add new fileserver features to helium release notes

Also made some formatting fixes
Fix usage of state.show_sls for salt-ssh
disable minion data cache
give better errors as to why the shim failed to deploy
better error message
set the wipe param based on what the sending command is
Allow archive.extracted to be used during highstate run

Use state.single instead.
Use better target cache dir. (Note that this may cause previously cached
files to be re-cached!)
don't create a local tmp dir on the caller
Catch attribute error if str
Missed one try/except
Guh. Wron exception type. Derp.
Fix rand_thin_dir
Merge pull request #16689 from thatch45/rand-thin-fix

Rand thin fix
Merge pull request #16690 from cachedout/issue_16658

Allow archive.extracted to be used during highstate run
fix issue with sys.doc and salt-ssh
Merge pull request #16668 from davidjb/2014.7

Fix usage of state.show_sls for salt-ssh