Tester for benchmarking run time
compare lex and parse times for samples

There seems to be some kind of bug in servo-style, since it barfs on
some CSS files.
cleanup tester
Add .gitignore file
Output benchmark as CSV
Initial version of spec library
Simple test of spec
Change naming in speculate lib.
Test specfold
Use Clone values rather than pointers
Benchmark `spec`
Benchmark some different sizes of vector