Update ctag documentation

Update ctag documentation of command line syntax.
Modify ctag capitalization to match http://ctags.sourceforge.net/
Add case sensitive search

Add case sensitive search when one or more of the characters in the search term
is a capital letter. (i.e. all lower case searches are case insensitive)

http://vimdoc.sourceforge.net/htmldoc/usr_27.html#27.1
Merge pull request #50 from salcode/ctags-documentation-update

Update ctag documentation
Merge pull request #51 from salcode/case-sensitive-search

Add case sensitive search
fixing some spelling mistakes
- added link to Git automatic configuration stuff for CTags
- turn off folding on markdown

This fixes issue #41 in which we were always opening markdown files and
they were completely folded. That sucks and now it doesn't sucks.