This commit improves Bash-It search functionality in a couple of ways:
* bash-it search (with no arguments) will print detailed help.
* bash-it search now accepts terms prefixed with '@' sign, indicating an exact match.
* bash-it search now performs smarter caching of the component listings/status
New search syntax is as follows:
bash-it search [-|@]term1 [-|@]term2 [ --enable | --disable | --help ]