Particle namespace cannot have numbers

Partner Rank:
3

Partner Team Reporting:

Spark Squared

Verification builds:

1.11 windows 10 

Summary:

Custom particles Throw syntax error when having a number in the namespace

Impact:

unexpected behavior when needing many particles with numeric names, having to spend additional time giving everything real names

Repro Steps:

1. Add Resource + behavior pack to the world (provided to Gregg in slack)
2. type /particle bug:report and notice the particle works
3. type /particle bug:1 and notice the same particle gives a syntax error

Observed Results:

Particle names bug:1 throws a syntax error

Expected Results:

A particle with a numeric id should not throw a syntax error

Regression Builds:

never worked for new entities