Swallow .baseDir.ts temp file deletion error statement

## Problem

With new task tree implementation, TSC tasks now echo a console error:
`fs: missing callback Error: ENOENT, unlink '/Volumes/CASE/code/wGulp/examples/browserify/src/.baseDir.ts'`

## Solution

Multiple tsc tasks can now operate concurrently, so it's possible that another tsc task will have completed and subsequently deleted this temporary `.baseDir.ts` file before the current tsc task completes.  The error pops up when 1 of these tsc tasks finishes and tries to delete the temp file, which no longer exists.

It doesn't adversely affect the tsc task for the `.baseDir.ts` to be deleted in the middle of its operation (only needs to exist at the beginning of the task), so we can just swallow the error.

## Testing (How to +10)
- Tests should pass
- Examples should still work and no longer display the above error in the console output from `gulp`

@evanweible-wf 
@maxwellpeterson-wf