Fix #183

The 'check_if_building' function did not return a boolean value if
a tag file was being built. This is incorrect. Additionally the
error message displayed when this case occured was not prominent.
Resolve both of these issues.

- Return False from 'check_if_building' if file is building
- Use 'error_message' rather than 'status_message' for more
  prominent dialog message
- Formatting of file to keep all lines under 80 characters
Convert 'opts' option to list

- Multiple arguments were not supported for the 'opts' argument. Fix
  this by using a list for arguments, rather than a string
Remove default case from "settings"

- The default settings value of '" "' for 'opts' causes issues.
  Remove this as it's not necessary.
Pretty print exceptions

- Exceptions are displayed using 'error_message' calls, but the output
  value is raw and not encoded correctly. Fix this.
Fix issue where value of 'opts' wasn't checked
Revert "Pretty print exceptions"

This reverts commit d54fe869278868741a311d11729121c0038bc326.

This modification can cause some issues and hence is not yet
ready for prime time. Revert until it's complete.
Merge branch 'bug/205' into development
Merge branch 'bug/183' into development
Modify tag regex to deal with tabs in 'ex_cmd'

- Integrate changes suggested by 'scriptkitz' for issue #209

    https://github.com/SublimeText/CTags/issues/209
Append 'r' prefix tag regex strings

- The tag regex is an example of a raw string. Mark it as such.

    http://stackoverflow.com/q/4780088
Merge branch 'bug/209' into development
Merge branch 'development'
Update Messages for Package Control