Fix tilde constraints without a stability suffix to work like wildcard constraints.

With this fix, a tilde constraint such as ~3.1 won't match unstable versions of 3.1,
but a wildcard constraint such as 3.1.* would.  This seems like a confusing
inconsistency, and so I have corrected it.
Refactor wildcard matching to use manipulateVersionString
Formatting updates for PSR-2 compliance.
Fixed lower bound of tilde and wildcard matches.

The lower bound of ~1.2 and 1.2.* style version requirements now uses >= 1.2.0.0-dev instead of
> 1.1.9999999.9999999.  This is more straightforward to read, and behaves equivalently.
Fixed upper bound of wildcard matches.

Follow-on from 95b4348afa2ee335d9dc1f9e2fecf579b49f7ddf
Merge remote-tracking branch 'sminnee/fix-tilde-constraint-stabililty'
CS fixes and one more test for safety, fixes #1855