Refactoring - Githubissues

Reorganize files to place all source files under src/ and all built files under build/.
Modularize XSL transformations such that common MusicXML accumulators and function go into musicxml.xsd
Rewrite timemap.xsl transformation to reuse the unroll.xsl script instead of duplicating it
Optimize the usage of accumulators for various XSL transformations
Rewrite mma.xsl to mimic the timemap.xsl method of first calling unroll.xsd then generating the MMA script
Add missing tests

infojunkie / musicxml-midi