Set CXX env var to specify suitable C++ compiler (travis)
Use CMAKE_(C|CXX)_COMPILER options
Use -fprofile-arcs / -ftest-coverage as compile option for gcov
Add gcov to check test coverages
Use coveralls to check test coverage on web browsers
Merge pull request #15 from rpcope1/master

Updated both libraries to use double instead of float.
Merge pull request #16 from gregtour/test-coverage

Set up for code coverage with coveralls.io
Improved the way error codes are passed through functions.
Increased precision of floatp print/tostring to 16 digits as double type.
Added Stack Trace on program fault and display line number of where program ends.
Also prints the syntax tree production for the failed instruction.
Edit CMakeLists.txt
Change to run test/run_test instead of test/run_memory_tests
Add tests for stdduck#PrintValue()

* output string
* output function
Run apt-get update on travis-ci
Fix indent
Move open-brackets
Improved LR(1) error messages.
Added <else if> to the duck context free grammar.
Rebuilt SLR tables for <else if> in duck.h/duck.c.
Added if/else if functionality.
Merge pull request #18 from gregtour/improve-test

Improve test