improve interpolate-source (with BUILD_DATE). Minor tweaks to Help Options:
  -h <topic>     Help - default topic is 'options'. Also 'tasks', or any task or alias name.
  -ht            Help - show tasks (and task aliases)
  -version       Print version
  -v             Verbose
Help Topics:
  options 	    default)
  tasks         lists all tasks and aliases
  <task-name>   task description, task options, and default values
  <alias-name>  lists an alias's task(s)
Tasks options:
  -+tasks=       Additional tasks to run first. See '-help tasks' for tasks list
  -t             Build cross-compiler toolchain(s). Equivalent to -tasks=toolchain
  -tasks+=       Additional tasks to run last. See '-help tasks' for tasks list
  -tasks-=       Tasks to exclude. See '-help tasks' for tasks list
Platform filtering:
  -arch=         Specify Arch (default is all - "386 amd64 arm")
  -bc=           Specify build constraints (e.g. 'linux,arm windows')
  -os=           Specify OS (default is all - "linux darwin windows freebsd openbsd")
Config files:
  -c=            config name
  -wc            (over)write config. Overwrites are additive. Try goxc -wc to produce a starting point.
Package versioning:
  -br=           Branch name (use this if you've forked a repo)
  -bu=           Build name (use this for pre-release builds)
  -pi=           DEPRECATED option name. Use -pr instead
  -pv=           Package version (usually [major].[minor].[patch]. default='unknown')
Other options:
  -codesign=     identity to sign darwin binaries with (only applied when host OS is 'darwin')
  -d=            Destination root directory (default=$GOBIN/(appname)-xc)
  -goroot=       Specify Go ROOT dir (useful when you have multiple Go installations)
  -include=      Include resources in archives (default=INSTALL*,README*,LICENSE*)
  -pr=           Prerelease info (usually 'alpha', 'snapshot' ...)
  -wd=           Specify directory to work on. go fmt.
flick version in goxc.go. removing a log enry