Merge pull request #8 from feilb/master

Change frequency to double to allow for time-accurate long periods
Merge pull request #9 from feilb/master

Add frequency=0 check; Fix bug where handler is called immediately on start()
Ignore file modified

added.DS_Store to ignore
Merge pull request #12 from colombod/master

modified ignore file (.DS_Store)
Improved the structure of the comments and their content.

* Moved function documentation to multiline comments.
* More information on what the most important lines do (source: datasheet).
* Spaces and Tabs where unified.
Merge pull request #13 from pklaus/code-comments

Improved the structure of the comments and their content.
README transferred to Markdown format
Removing warning for hw pins. Closes #11
Merge pull request #15 from pklaus/markdown-readme

README transferred to Markdown format
Adding documentation about the hardware of the Timer Counter
Merge pull request #18 from pklaus/adding-documentation

Adding documentation about the Timer hardware
Minor readability improvements
Technical Cleanup:

* Setting up the frequency (and thus enabling all timers)
  whenever the library is used is selfish:
  Maybe someone else wants to use one or more of the
  Timers/Counters in his code for other purposes.
* We don't use the register RA and its triggered output line
  TIOA in any way, so we don't need to care to set it up.
Merge pull request #19 from pklaus/readability-cleanup

Minor readability improvements in the source code
fixing bug: check in start() if _frequency is > 0.
bug fix for 876a136  -  thx @ivanseidel
Merge pull request #14 from pklaus/technical-cleanup

Technical Cleanup