Adding single and double click support

[jdavidthomson]

Linked from breezy-desktop issue as implementation was in the XRLinuxDriver:

wheaney/breezy-desktop#11

I've worked on updating driver.c multitap.c and output.c programs to make 1,2,3 and 4 taps work pretty well.

The constants have been updated in my code, and calibrate and center have been pushed down in priority, making room for single and double tap.

I implemented the single left click, and double left click using using the appropriate mouse driver code.

Will submit a pr eventually.

[jdavidthomson]

PR Submitted:
#51

[wheaney]

Closing since the PR was closed.